"The factory shipped those tractors with a single carriage bolt in one of those holes, and the owner's manual showed a claw hammer being used with the bolt to pull it tight. That's how I always did it anyways. "
Yeah Bern, but I had to take the compressor off anyway, and this works pretty well. This makes it easier to keep the compressor squared and tight as you tighten the mounting bolts.
Reason I took the compressor off was to replace the bottom mounting bolts with studs (just 3/8 all thread) and nuts as I was loosing refrigerant and oil from one bolt hole when I would loosen the bolts to adjust the compressor belt. Smeared the threads with permatex #2 before assembly, hopefully will take care of it.