On my 85 c10 the A/C was removed. I bought the truck and had to put it back. Ended up going with the factory compressor setup to keep costs down. There are after market kits and places that make custom high pressure and low pressure lines. Vintage air makes a smaller unit , and has some different brackets. Look around find out what have you found, and what do you need.
When I was putting it together one thing that I had trouble with was the accumulator .Was told it needed to be a 134a and the original replacement was for r12. I looked everywhere for a 85 accumulator superseded part for the 134a. Turns out it was the original r12 accumulator all along, and only required the adapter 134a fittings.