Clear up the A/C questions

[LS1GMCTruck]

It is the truck water pump, and the drive by cable. So why can't I just use the full setup out of the donor truck?

You can if you clearance the frame enough for the compressor and fittings & lines. You can bolt in a complete truck engine as-is, after you do that. I misunderstood you. I thought you wanted to use the truck compressor up high on the passenger side. Or if you want to try and make brackets that will hold your trucks original compressor down low, you can try and figure that out. But I don't know of anyone thats done that. It might also need to be mounted upright, in its original orientation, due to lubrication needs...I don't know.