A couple of more comments on cab disassembly:
Gas tank came out ok and looked pretty good except for the additional 5 lbs of dirt underneath it. Then noticed that the back of the cab had a rust hole and after closer inspection realized it went almost all the way across. Another patch panel.
Seat frame was a PITA to remove. I have a spot weld cutter and a good quality 5/16" drill bit but due to the upper lip on the frame it was very difficult to get the right angle to cut the spot welds. They were also very difficult to see even with wire brushing the rust off!
Finally used the trusty grinder/cut off combo and sliced the frame at the floor and then went back and removed the remaining strip. I've used the spot weld cutter before and have had good success with it but after putting some additional holes in the floor I decided to cut the remaining strip off between welds and cut the welds parallel with the floor pan!
It seems to me that the seat frame was also a stiffener for the floor pan. I'm thinking that some additional 1' x 1" square tube between the rear supports and around the front supports and tie them together will restore the floor stiffness. I maybe using late model Blazer seats and console so I will need something to tie them to.
Removing the pieces to the dash was slow due to the dirt again and everything being rusted together. I knew the steering column support was toast but I didn't know how bad.
The support brace was still bolted to the firewall but was broken at the dash. The dash has multiple fatigue fractures and the under dash bolt/mounting bracket were broken free! In other words many miles of rough road and constant pounding. The steering box was tight and unbroken but everything else in what was left of the front end was worn out.
Went to stovebolt.com to figure out how to remove the steering wheel and short of fabbing up a puller I tried to pull it from the steering box!
The column will not pull out of the worm gear but by backing out of the worm it will free up the outer part of the column. Using redneck engineering I removed the horn button and backed off the nut until it was almost off and using a BMFBPH I gave it a few whacks and separted the steering wheel from the column! Then removed the steering box from the frame and drag link (which was so worn out it fell off the pitman arm).
By comparison the front end was easy!