Rear Template Mounts

I got a little carried away cutting the floor up so there is some patch work that will need to be done. Now that I know what I am doing the other side will be much cleaner. I originally thought that I would need to notch out the interior panels to fit the control arm bracket but as you can see in the other image that won't be necessary.
 
For anyone interested, I have been using this pdf document of the corvette C4 frame pick up points as reference. the frame on my 65 mustang is very different compared to the C4 frame so its a little challenging to come up with the right mount points on my car.     

After two kids and two moves I left this blog behind. Unfortunately, a lot of things took priority over this project as well. I am just now getting back into routinely working on this project so I thought I would try to get this blog caught up. Currently, I have been putting a lot of work into installing the front and rear suspension from a '91 C4 Corvette. I received a few emails from some folks doing a fastback conversion like this which I hope to respond to in the near future. I apologize for taking my time but better late than never I guess. Most of these pictures are from the suspension swap The fist few were taken about 4 years ago in my newly remodels garage. We have since moved form that home in Idaho. You might notice a little more rust on the car. That's because it rained on me during move from Idaho to Oregon. Yeah I probably should have done a better job covering it but I took a chance and lost. Luckily it's only flash rust so it can be dealt with, it's just more work. The C4 suspension is a little wider than the stock 65 mustang which is why I chose to go with these flares. I got these fender flares from here It was so long ago I don't even know if they sell them any more. If you are interested in them, I suggest contacting them. In addition to adding width to the car the flares will allow me to cut a larger area around the tire so I can give the car a lower stance. I started designing the front coilover mount on the computer. There was no real science involved in selecting the location of the crossmember. I had to make a small notch in the frame rails to accommodate the crossmember. One issue I am still working through is notching the frame to make clearance for the steering rack. I wanted to check the strength of the mount so I backed calc the maximum load the mount could expect to see with some additional safety factor. The springs I'm using are 375lb which means the force to completely compress the spring (where are the coils are touching) is close to 1300 lbs. Since I plan an installing bump stops the mount really shouldn't see more force than that. I shock would also exert a force but I didn't bother trying to figure that out. instead I just times the maximum amount by 2 then rounded it up to an even 3000lbs. I'm lucky enough to work for a metal fabrication company which give me easy access to a laser cutter. This is probably one of my favorite perks at my work. I cut the parts out of 1/4" mild steel plate then proceed to weld them together.

I'm only tacking everything in for now. Once the front and rear are in I plan to take it to body shop and have it aligned. If everything checks out I'll weld it all in for good, but if I have to make some changes I only have to grind on a few tack welds.

It been a long time Since I have put a new post in here so I thought I might add some pictures to up date my progress. Most recently I got the car sandblasted and I have since painted the under carriage with POR 15. We are soon to be first time home buyers and I am finally going to have a garage of my own so I hope to be able to spend some more time on this project.
I also replaced my trunk floor panels along with the driver side quarter panel. The quarter panel I bought from a local guy for a good deal. Unfortunately it was was for a convertible. But I manage to make it work. After going through the trouble though I might suggest it to someone considering this type of project, just fork out the cash and buy two reproduction fastback quarter panels then you have less chance of warping and what not when you go to weld it in.

Cowling repair

Here are some pictures of my cowling repair done after I converted the mustang from a coupe to a fastback. I went to my local harbor freight store and purchased a spot weld remover drill bit $6. I would recommend buying a spot weld remover drill bit if you plane to remove the cowling cover. There are about 100 plus spot welds that need to be removed. It took me the better part of a week (putting in a few hours every other day) just to remove all of the spot welds. once I was able to remove the cowling cover. I was pleasantly surprised to find only minor surface rust in an area that is typically rusted through. I cleaned up all the leaves and wire pushed the entire surface. Then I completed the 3 step POR 15 process of washing with degreaser, then using the metal ready, and finally putting a coat of POR 15 on and covering it with primer. I really like using POR 15 because it dries rock hard and locks out all moisture. This repair should ensure that the cowling won't rust out for many more years. Make sure to cover over the shot welds with painters tape so you can realign and weld the cowling cover back in the right place. I will use weld through primer over the spot welds to prevent any rust from forming in the seam when I weld the cowling cover back on.

Cowling

Removing and Test Fitting

Once the back part of the roof was free from the car most of the cutting work was done. The tricky part came from trying to match up the new fastback roof with the car. We first began by cutting the side of the fastback roof about 1.5 inches down along the top seam of the quarter panel. Next we removed what was left of the front windshield on the fastback roof. Don't forget to use a torch to melt all the factory lead filler around the seam. I will go back over with body filler to replace the lead, but I only removed what I had to, to get to the seam. It is important that you pay attention to the front of the roof when you cut it. look closely at the factory seams. While looking at the car with the coupe roof still attached in the front, you notice how on the side supports of the windshield in the top corner just before the metal transitions to the roof there is a slight bevel. We used this bevel as a guild to make sure we lined of the fastback roof in the right spot. It was simple to make these cuts but hard to make them at exactly the same angle for both the fastback roof and the coupe roof. We ended up having to fill in about a 1/4" gap with weld on the inside of the roof support. Check out the diagram in the picture, you should be able to line up the front of the fastback roof exactly with the bevel at the support transition.

A lot of minor cutting was made in the rear of the roof so that it could be set in right. The rule of thumb we played is if it was in the way then it had to go. Just take your time and make what ever adjustments you need to in the rear so that the seams line up. If you do the front of the roof right the rest of the roof should just about fall into place with some minor adjustments. It is also helpful to have a buddy at this point so one can force the roof in place while the other tacks it in. It is also helpful to have someone sit inside the car a force the quarter skin out so it makes a tight lap weld along the quarter seam.

Well that about sums it up for the dirty part of the conversion. My next goal is to get new quarter skin and replace them, so I will have to go back over my lap weld. Currently I have the car on a homemade rotisserie and I am beginning work on the cowling and under body so I will have more on that later. For now I will just include some more pictures that I have taken during the conversion.

Under the Knife

There is really no other way to put the next phase of this conversion. At this point we took a step back and evaluated the best way to remove the roof. We had to consider that our main cutting tools were only a 4" cutting wheel and a large flat head screw driver which we used as a chisel. I would recommend a sawzall if you have one though. We began from the back of the car and worked our way forward. I first marked a line approximately 1" below the edge of the rear quarter panel. This is where we will separate the old roof from the quarter panel. It will make for an easy lap weld. I will have to replace the quarter panels on this car so I will go back over this part once everything is fitted in place and cut the over lap off and make it a butt weld. I read that a butt weld is stronger and if you ever replace your quarter with a quarter skin you need to butt weld it in place. Should make blending easier too once the body filler is applied.

The next major chunk to be cut is the rear trunk section. At first I though I could remover this part with the roof as one piece but it became clear that we had to take it in steps. There were a lot of layers of pinch welded metal in this part. A sawzall would have come in very handy right about now. This part is the most time consuming of the whole conversion. After we removed the the rear trunk section we moved on to cutting the rest of the roof away from the rear quarter panel. At this point it got very frustrating trying to cut through all the main support in the rear of the roof. Like I mentioned before all we used was a 4" cutting wheel so we didn't have very deep penetration. Finally the entire rear section of the roof was free. All I can say is use you best judgment on how much you want to remove on this section. I recommend looking at some interior shots of original fastbacks with out the interior panels (just google 65 fastback restoration pictures). From what I saw the coupe is much more supported in the rear of the roof than the fastback models so don't be afraid if you feel like a lot of it has to go. I guess it also depends on how much of the fastback you have. Mine actually included part of the wheel well so I pretty much remove every piece of support from the coupe roof and just used the support from the fastback roof.