My truck has been stripped from all of its a/c components from somebody who owned it before me. I need to buy A/C brackets and i need to know which ones to get; either for the long or the short compressor. I can get either compressor that has been rebuilt and changed over to R134-A. So it doesn't matter which one i get. So my question is do i get the Long (A6) compressor or the Short (R4) compressor, is one better then the other? This is going in my '78 K10 with 350.