Factory A/C in 1967-1972 Darts

The RV2 works well and is reliable, but quite a beast. Definitely don't buy factory AC parts for a non-AC car since it won't fit (firewall differs, post above). If you have a factory AC car, you could install a modern Sanden compressor to work with your existing climate box and evaporator, since lighter, smaller, and cheaper than a rebuilt RV2. See Bouchillon performance for brackets (or a post here for slant-six options). I would re-hose with modern "barrier hose". You can cut off the factory crimps to re-use the fittings. If no Mastercool crimper, can use Oeticker stepless ear-clamps, PEX clamps (some sized), or Breeze screw clamps. If changing to a more efficient parallel-flow condenser, I would use O-ring fittings except at required factory connections. With a Sanden, you won't need the metal suction bottle.

I use HC refrigerant (Duracool, Envirosafe, ...) in all my vehicles, even a 2002 Chrysler. It is compatible with factory mineral oil, but I use better PAO 68 oil (Duracool's Oil Chill). R-134A is being outlawed, R-12 is pricey ($100/can), and current R-1234yc needs different pressures (and pricey). Many claim/imagine that HC refrigerant "can explode", but they didn't take graduate course in combustion like me. No fire reported in the millions of cars which have been using HC for many decades, and it has been in refrigerators in Europe for decades. Carrying a newspaper in the cabin is a greater fire risk. All new products raise alarms from naysayers, like the silicone brake fluid and waterless coolant I also use. People once called chicken-little about electricity in the home (touch it and die), HEI ignitions, and one columnist even claimed electricity from a nuclear plant is radioactive. Science is tough for most who prefer belief.