I riveted my -7 rudder bottom fairing, then glassed it in place. I ran the tail position/strobe wire back into the fairing with enough length to pull the connection all the way through the back of the fairing. I've had to change my position/strobe light from Aeroflash to Whelen - didn't have any issues with the wiring or the fairing!
I don't see any advantage to being able to remove the fairing. I glassed all of my empennage fairings, and installed nutplates/screws on my wingtips.