Ernie - I've got my compressor under the battery box per the instructions. However, you may want to consider mounting somewhere else as suggested by other members. First, cramming all the wires and the primary air line into that tiny space seems crazy. I worry that something eventually is going to get pinched. Second (and maybe just peculiar to my bike) there's a fender bolt that interferes with the pulling the compressor into location once it's lined up in the "v groove" on the bottom of the battery box. Since the space is so confined, I couldn't get a dremel or anything else in there to cut off about 1/4" of the bolt for clearance. I had to pull the blade from a hacksaw and cut the bolt little by little. Major pain in the $#@!!! So if i had to do it over again, I'd find another accessible location. On the plus side, the unit works great. PJ