Joe, I've got one in exactly that spot. Its taped up and out of the way to the brake light wires running down the passneger side. Then again, mine could possibly be for a rear window wiper and defrost that would have been wired for a hard top. Anyway there is a harness there but nowhere else in the back that I can see. I've got all of the plastic panels pulled off of the back right now so it would have to be pretty well hidden for me to miss it.
-j

when looking for a container to hold drained brake fluid, find a container that is different from the beverage you are currently consuming.