POST 1: VINTAGE AIR FIREWALL MODS
I started the swap with disassembly and modification of the firewall to install the Vintage Air Gen IV Surefit kit. Out of the box, it uses a metal plate to cover the holes left by the old A/C suitcase. Unfortunately, the panel didn't cover all of the holes completely, and it was designed to be held in by cheap screw in fasteners.
(notice in particular this hole is about half uncovered)
I wanted something that was going to look a bit cleaner once installed, so I ran down to Ace and bought a handful of 1/4-20 buttonhead bolts and matching nuts. I ran the bolts through the plate and firewall, and then tack welded the nuts to the backside of the firewall so it was permanently threaded. I also used a few of the extra pieces of metal that came out of the holes cut to pass through the new A/C and heater lines, and welded in a few of the unneeded holes, including the one that wasn't fully covered by the plate.
Preparing to tack weld the nuts to the firewall:
View of tack welded nut and filler metal ready to be welded in:
Welded in:
Ground smooth:
Bare firewall after mods:
Brackets sandblasted and unit installed for test fit:
Mock-up of PCM mounting:
With the firewall welding complete, it was time to turn to stripping and painting the interior...