When I put the current TSP engine into my 70 GS, I removed all of the factory A/C pieces. It was leaky and didn't work particularly well anyway. I would like to put the A/C back in, but I would rather use the most efficient modern components available. Not sure whether I should reuse the factory evaporator, or replace it. Is there a more efficient replacement available? If not, can I have my original checked over? I will go new for everything else. Again, are there more efficient condensers, compressors out there, and if so, who has the best prices? Can I make it cycle like a modern car? What is the advantage to the Sanden compressors? Are they more efficient taking less power to run? Looks like they are smaller, and that is a definite plus for me.