Welcome back after almost a year...
http://www.irv2.com/forums/f53/conne...ml#post2218541
As stated before, the Tailgater needs a coax to carry the Raw SAT signal in and low voltage out for the Tailgater's auto-aim feature. I would just add a coax line from where the SAT receiver sits to an area under the RV to connect to the Tailgater. The fascia next to the windshield is removable to get the coax down from the overcab cabinet.
If you do not want to add a coax, then you can repurpose the cable-TV coax in the electric bin...either move it permanently to the receiver or put a simple A/B switch at the interior end of the coax and run 2 new short coax cables, 1 to the Quest video selector -and- the other to the SAT receiver.
Ensure the A/B switch has no amp or similar circuitry that could mess-up the raw SAT input and low voltage output.
Best luck