Classic/Antique Car Repair: powerglide, vacuum line, engine vibration

Question
I have not worked with auto trans before. I'm putting one in a 1972 chev 1/2 ton . What dose the vacuum line on the back of the powerglide hook up to. And do I have to mount the rear of the trans. on a rubber mount.

Thanks Ray

Answer
The vacuum line is connected to the intake manifold of the engine to read engine load via vacuum. This system limited the throttle rod function to just signaling passing gear rather than signaling throttle position for gear shift points. The vacuum now controlled shift points. As far as the rear mount goes, the purpose of the rubber in the mounts is two fold. !. To allow the engine and transmission to move slightly for alignment and 2. to eliminate engine vibration up through the vehicle. Yes there should be a rubber isolated mount at each mounting point.
Brad