If you have a 305 with a A/C bracket already. Use it where it is. You can't just swap sides. The brackets you have or the brackets they supply won't work. Hoses run from the compressor to the bulkhead adaptor plate. That adaptor is a place to mount bulkhead "connectors/fittings" to receive the outside hoses and, I assume, on the inside there are hoses to the evaporator. Your only issue is if you have to buy some universal hose kit from them to reach. The A/C is designed for Chevy. For what motor? I don't know. From what I see, that's my opinion.
P.S. The picture in your link does NOT seem to show all the A/C hoses needed. Better call them, tell them hose kit not shown? and is NOT mentioned?
This
Pic shows it and the manual says 60-63.