Why would you "start from scratch" with R12?

Properly sized components work great with 134a. The cost of the components for a system is really no different for either refrigerant. The cost of R12 vs 134a is significant however.

Many of them had straight fittings like this one:

https://www.autoacforum.com/messageview.cfm?catid=2&threadid=31064

But I think they went to the brazed pipes to get away from the 135 degree hose fitting. Pipes are more robust and cheaper.

Those are brazed in to the body. Don't try to remove them.

Check the cam surface, and pintle for wear. Check the cam pivot too. Lubricate the pivot with a tiny bit of good oil, and the cam surface with a thin film of wheel bearing grease.

Much better to replace the fittings.

Look here - the pages flip for miles in either direction:

http://fs1.omega-usa.com/ALTCatalog/#?page=380

Then contact the site sponsor to buy.

http://www.ackits.com/
602-233-0090

Again.

What type of oil, how much, and where was it installed?

How much 134a was charged in to the system?

The A5 with the Hot gas bypass worked well. The valve is an easy rebuild, sometimes the cam & pintle are worn. An A6 conversion probably works ok, never messed with one. Are you usure of the hose routing? Pics in this thread: https://www.autoacforum.com/viewtopic.php?f=3&t=331 Finally how mu...

Well, since most of us don't have a wind tunnel, we find other ways. The physics of a refrigerant gas make it predictable at a given temperature. As long as the system is above 50f there will be both liquid & gas. The P/T relationship will affect the gas pressure, but the liquid volume change ov...

The York compressor is probably geared down to suit the application - how big is the crankshaft pulley? Any direct mount compressor could be adapted to that mount - but direct mount compressors tend to have serpentine belts so a clutch change would be needed. A V5 for instance would be a great choic...

Forget the silly to tap junk.

http://www.ackits.com/85530-3-in-1-side-mount-can-tap-us-standard-31770?keyword=side%20tap

No matter what size the can is, or what is in it. Just side tap it.

Well, outside of the obvious air leaks on the evaporator box you need to deal with, there are a couple of other issues. 1) The cycling switch hysteresis. This is a problem I have seen with this vintage Ford before. It should not be waiting for 60 psi to turn back on. It may also be responsible for t...