VIN says it’s a 68 RR. Fender tag is beyond reading. Stampings on the core support and rear trunk lip match. Has a clear title with same VIN. Seats have never been removed or anything so a build sheet could be in it if the rats haven’t eaten it. Engine and trans are with it and supposed are original but I haven’t gone that deep yet.
Many many years ago, I too-had a 67 Coronet, 4 dr 383-2 bbl. I bought it from my uncle with a blown up engine. I put another 383 in it, got the AC running. It would blow frost flakes off of the metal vents. People in the back seat would always ask me to turn it down! I really believe the 66-67 B Bodies had well designed AC units in them, better than a lot of others. I would revamp one of them before I would install an aftermarket system. And the heater would boil your ass off also. Might go with the Sanden compressor though.
A 383-4bbl four speed A/C car was possible and they are out there. But because you can't cross reference two items (four speed AND A/C) production figures are not known. They are certainly 'not common' and 'hard to find'. In '68 and '69, this combination would have received the 330 horse version of the 383-4.
My parents bought a very early 68 Road Runner with PS, PB, AT, and A/C. In Fresno, A/C is mandatory. Everything worked great. I drove it to high school. I was just a few months short of my H.S. 10-year reunion and I really thought it would be cool to take it to the reunion, but I sold it instead for $600. Probably most of us have some of those kind of regrets. I do think that a 4-speed with A/C would be very rare.
My ‘68 RM21 4 speed was an ac car and also had no power steering or power brakes, was a decor package car and was also LL1 turquoise. This was all obvious when I was drilling it apart at the spot welds but no fender tag or broadcast sheet.