I am installing A/C on my 40 Chevy Coupe as well. You are a step or two ahead of me. So far I have installed the condenser and compressor. I have a GMC engine. I made the compressor bracket which looks like the one you have and I attached the condenser to the radiator frame using homemade brackets. Currently I plan to mount the cooling unit under the dash and figure out the hose layout. I bought a Souther Air unit. I want to make sure that the front end is easily removable with minimum interference from the A/C hose lines. Did you run both the heat and A/c lines through the kick pannel? How did you direct the lines from the condenser back to the compressorand dryer? Did you cut hole in the sheet metal?
