[silverbear]

My 86 started out as a non A/C cab. I pulled all the necessary components of off a blazer that was getting scraped so I could convert. The hole in the firewall is different and I started to make a pattern off of the Blazer firewall when I found a replacement cab with A/C. My original cab was more rust than good metal. To convert to the OEM setup it is a bit more than just swapping out the blower motor box in the engine bay. The controls are different. The manual kick panel vent setup on the pass. side get replaced with a vacuum actuator and there is an additional actuator and flap to install in the rain gutter on the passenger side.

Having said all of that, it would be cheaper to find OEM parts to convert with a little bit of cutting the firewall. The engine compartment looks much cleaner with a system like what Vintage Air offers. The V.A. system has a better blower motor but that system will hurt the wallet pretty bad.