then it must be okay not to mount the compressor on the engine. At least for your setup. Ours hangs off the 'beke and it makes a PITA of reaching the raw water pump (even with a SpeedSeal). But I like the holding plate and we usually need the engine once or twice a day, heading to a new harbor, so there's no wishing we had a 12v unit. As SG asked, what are you swapping the SF for?