I taped mine temporarily to the front fiberglass window cover on the TT and moved it a couple of times until I could see it in my rear view mirror. When I was happy with the location, I drilled 2 small holes in the window cover and mounted with small, 1/2" long, stainless steel bolts, washers and nylocs. It is not centered in the cover, it is directly behind the drivers seat. Works well for me.
2001 Ford F-350 Super Duty CC Dually, 7.3 Diesel
2011 Cedar Creek 36CKTS Touring Edition
Full body paint, Cummins Onan 5500LP, Andersen Ultimate Hitch
We were on the road to ALASKA May 6, home Sept. 13, 2016. 23 states, 3 Canadian Provinces, up to the Arctic Circle, 17,300 miles, 131 days on the road. 1 flat tire, 4 oil changes. What a beautiful trip!