Shop/garage heating & cooling: what'd you go with?

[Chevy454]

Clill: ours is almost the same size, 60x100...is your ac/heat unit overhead, or standard fare house furnace? I see your ducting overhead, which is basically what *I* have in mind...but when we've asked some local "contractors", some say waste oil, some say propane overhead, yada yada...I'm doing a ground source system just across the field for our new house, and I was originally gonna tie the 2 places together and share part of the lines since we have to have so many hundred feet of them anyway, but noone here seemed to have a clue if it was possible or not...?