Has anyone done this? Looking at options to install A/C in my 74. What about the entire dash assembly as well? Not really what I want to do but it may be an option.

Not really what you are asking but i installed a 90 system into an 85 crew cab. But these trucks are the same on the inside. The opening on the fire wall is different on your 74.

Yeah I know the firewall opening is different but that isn't any thing some sheet metal can't take care of.

I sort of did this, just heat though on an 80.

The box fit the firewall and kick panel without much effort.

But the 81 up ducts are molded to fit the 81 up dash, vs hose for the 70's stuff. So...

I swapped the newer dash, which I don't recommend. The only holes that lined up were under the windshield. The lower corner bolts are nowhere near the right spot and the steering column mount is slightly higher on the older truck.

Then there's wiring, the newer ammeter is not compatible with the older wiring.i ended up swapping the wiring harness as well which has a different bulkhead connection.

Remember, this was heat only, ac probably adds more headache.

I am pulling an Hvac system out of an 86 truck cab next weekend if you want it. I will donate it.

I will be blocking off the hole so we could also cut a piece out to get the correct hole to bolt into your 74 once you cut a patch out of it. then just graft it in place.

I had a 79 4x4 that I junked a while back and it had a mid 80s dash installed in it.

IIRC, they bolt in the same bolt locations only the frame/cover/harness changed. **** I did not look at it that close enough to remember how it was in there.

mid 80s has the 2 lower side bolts/ one bracket in the middle/ and screws across front edge under gasket.

Way back I took the a/c unit from a 75 a/c truck and installed it in my 77 non a/c truck. I cut the 3 dash openings and the controls fit fine. As I remember the cowl was the same. You just about need the windshield removed to do the dash frame swap. 72-80 would be a shoe in. 81 and newer everything is different.

That would be awesome Mike. It would give me an excuse to come up and visit with you as well. Just let me know. Thanks.

any time you are ready. I have the cab on a trailer at the house now. I will be stripping stuff off this weekend.

off work Friday & Monday this weekend.