Firewall and fender aprons

With the body finally back home and replacement panels at hand the project is ready to go ahead. I planned and decided the order of the activities so that I would replace the sheet metal where ever it is possible to do without tearing the car apart. That is, I wanted to add rigidity to the unibody. The floor pans are so weak and I was worried about the body sagging between the cabin and engine bay unless they were not supported. As a matter of fact the front of the car is connected to the rest of the car from only few places. The frame rails (or the frame rail extensions) are welded to floor pans and the fender aprons are welded to the firewall and that's about it. Now that the firewall is pretty rusted out and the floor pans are almost gone there are not so many spots that connect the parts with each other. To add rigidity easily I figured starting here would make the best result with less effort.

To fix the firewall outer ends with partial firewall outer ends you need to remove the rear fender aprons. The rear fender aprons are spot welded to the shock towers, frame rails and to firewall. Before the removal of the old passenger side apron (date code 10 10D2 and another 10 6 3D on it) I documented the positions of the fender nut slots. After drilling out the spot welds this is what you get.

Now that the apron was gone I was able to define and draw the line where to cut the bad part of the firewall. Luckily this happened to be near to the line which will be covered with the new apron.

The firewall was cut along the line and the patch panel was fitted so that the excess material could be cut. Once the fit was acceptable it was welded in. It appeared that my Mig-welding skills had also some rust due to lack of practice but hopefully they'll return while the project continues.

At this phase I did not pay too much attention to the side cowl panel which can be treated later. I painted the newly welded seam after it had been ground smooth and after the rust had been ground off of the revealed areas. The next day I spot welded the apron. A hint for positioning the apron: have your coil spring covers at hand to define the correct vertical position. The replacement panel is not as perfect fit that you would expect and needs some modification. If it looks good does not mean it's correctly positioned.

Passenger side done

I do not yet have the apron bracket which connects the apron to cowl panel so I proceeded and repeated the patching on the driver side using the same process. The driver side apron seemed to have date code 16 102D near the VIN number. I am not sure if this is the date of manufacturing the part or when it was welded in the unibody. If the latter, then it is funny to notice that there was almost one week between the install dates of the two sides.

The steering column was removed...

...along with the steering box.

Much better seam this time

And hey, why not use clecos if you have some! It took some time to find a local supplier for them. I drill the spot welds with 3.25mm pop rivet drill bit before using the 9.5mm spot weld cutter so the 1/8" clecos are great fit.

The clecos are really helpful

The first replacement panels are there. I'll finish the seams and paint the front later when I'm done with all the patches.