Todd, thanks for the advice. I know that you learned from the school of hard knocks about rusty cowl panels. Like I said before, I have right clicked on several of your photos to save them. Several were of the cowl panel.
I talked it over with my neighbor who helps me. He is still insistant the we continue to repair the panel. He argued that the sheetmetal for the repair is cheap (actually free). And I keep thinking that if I completely mess up the panel, I can cut the cowl panel out and buy a new one. At least this is not a life or death decision.
I decided to contine to repair the panel. It would be good experience and I have lots of time. There is never a point of no return. I can always cut it out if it looks like a Frankenstien repair.
The first thing was to cut out the windshield wiper area rust. I learned on this forum that the wiper motor can be relocated to the driver outer shoulder panel. The fender hides the motor. I might try this.
This gave me access to weld the botttom patch.
The next step was finish removing the upper dash where the VIN number is located. Measure and mark and photograph it's location. Then drill out the spot welds.
Now I sand blasted the front again. It was easy to clean the rust from the inside of the dash with the upper dash panel removed. I used to sand paper to remove the rust from the under side of the cowl panel.
You might notice in the above photos that the jig's cowl bracing was modified. The top horizonal tube was changed so that it can be removed with two bolts. The driver's vertical support had an upper and lower square flange welded to it so that it can be removed with four bolts. With these modifications, I do not need to remove the entire assembly just to work on the cowl. The assembly still supports the passenger side cowl assembly.
Weld the upper patch panel. Plug welds at the top, very small stitch welds at the bottom.
I had to use the hammer and doly to form the bottom patch to the panel.
I smoothed the bottom patch with Evercoat fiberglass filler. It supposed to be water resistant.
Prime the cowl, inside dash and windshield. With the big hole in the cowl is was possible to spray the area inside the cowl panel. The top patch panel will be completly covered by the upper dash panel.
The hard part will be to cover the wiper hole. This is the part I am worried about.