Question.
1. Has it had left right conversion.
2. Cant remember AC for 71 but it will require at LEAST either a new Reciever Drier or an Accumulator.
Rec drier's are pretty straight forward, but if its an accumulator style system then research and get a Holden type which is set up for RH drive - ergo AC is on LH side, you will also need a new pipe/hose set up.
Don't throw away old pipes, hoses fittings, crimped fittings can be cut open and reused with a new ferrule.
Just did a quick look - its a POA type system, requires a new Reciever Drier, maybe a POA valve and or an expansion valve.
R12 is no longer available, and its replacement R134A is being phased out, there is another rather long winded Gas or you can opt for Hi-Chill -30. I've used this in two (2) C4 90's and soon in a C4 87 and hopefully down the track in a C3 78.
Hi-chill is effective, runs at lower cylinder & compressor pressures, does not require any special stuff, it is effectively a drop in replacement for R12 or 134A and requires far less volumn of gas.
If you take it to a good Tech, he should flush out and clean everthing, that includes oils, dirt etc etc he will then measure into each component an amount of new oil (I think a PAG Oil) make new lines, connect up, vacuum down, then if no leaks recharge with gas.
Then you will be cool. As long as the under floor insulation and underfelt and carpet has been replaced and of course there are NO holes anywhere in the fire wall. An 1/8" hole in the fire wall even with carpet over it will heat the cabin up to an inferno. Good luck.
