Square A/C cab v/s non A/C firewall compatibility ?

[Fastereddie]

This is great info.

 

[tarussell]

This is great info.

Ain’t it though !
I did some search’n before I posted up and there was a good bit of info about going the other way but not from hot to cold cab remedies.

 

[ipc838]

I have converted my cab to an ac truck and I will do my best to explain and not over complicate. The blower holes are in the same location but the heater hose holes and the evap coil holes are different. I have all the ac boxes which helped me make a stencile from card board.View attachment 462201View attachment 462202View attachment 462203View attachment 462204View attachment 462204View attachment 462205View attachment 462206I started by loosely mounting the new box and getting an idea of where everything goes. In the second pic you can see in the bottom right corner the stencile I used. I basically laid the under hood box on it and traced the out side. Including the screw holes for reference spots. Then did the same with the under dash box.View attachment 462209I just got home from work and found the stencil. I put the inside heater box and the outside one on and off several times to check fitment. Couple tips for you. The rectangle hole will need 3/8 pieces of metal to give it rigidity.View attachment 462210this was done on both sides of the hole. Stock cans this is all molded in. Second tip: the hole you weld up is on stamp metal which is already under stress. So when you cut it will probably warp just from releasing the stress. And when you go to weld the hole you don’t need this will cause even more warpage.View attachment 462211so get your self one of these and put a flange all the way around the new metal before you wel it back in. I wish I did it this way but I butt weld things all the time without issue and ended up spending a lot of time shrinking the metal and messing around with it to get it straight.View attachment 462212here is a pic of a peice I made for my fire wall with a flange.
If there is someone on this site that has the knowledge to turn my stencile into a printable file I will send it to them just let me know.
Also I have measurements in pics I will also post from a cab that is an ac truck.

Hi Mark, I am about to do this project on my '78. If you have a way of sharing these pics that would be really helpful for me. Thanks for the write up!

 

[Wes Harden]

Welcome to CK5 @icp838.
Few move post and you should be able to see the images.
Premium membership will allow you to see and post images immediately. Plus member only section well worth the sub