How does the TXV attach to the evaporator?
LOOK!!!! Another question without any information.
My 1943 Supermarine Spitfire doesn't have a TXV
.......and neither does my hemi Farmall......
So maybe you can tell us what it is that you are actually working on?
Bet that is squirrelly at the end of the 1/4 mile.and neither does my hemi Farmall
If this is a factory bone stock 70's Mopar A body with factory AC the TXV screws right onto the evap fitting with the appropriate O ring.
You have a factory service manual? Parts book? go to MyMopar and download one, free. You will have to stomp around in there because they have re-worked the website
I'd say it's a simple matter of having the correct parts. The 74 and 72 I'm sure are different. Again if you go to MyMopar you can download service/ and parts manuals I have a parts book from a 74 but not 72 If you have a way of adapting them, and are not terribly concerned with absolute "correct" I would not hesitate to cut/ silver braze etc as needed.
I am from over a decade, in a previous life, of stationary HVAC/R equipment, where most all TXV's were either flare (SAE 45*) or braze fittings, and wish the auto industry had done the same
Of course nowadays, even in the stationary equipment end, getting replacement parts for R12/22/502 systems is pretty much impossible