Contact Jayco. They provided a wiring schematic for me. It made hooking up my DirecTV Whole Home system easy using existing internal wiring.
As a side note, I wouldn't try to install any new wiring or DirecTV now even if you can't use existing wiring. My neighbor is a supervisor with DirecTV and he told me they have a couple of test markets operating right now where their servers and clients are wireless. He hasn't been notified yet when it will roll out nationwide, but he did say it was working great.
2006 GMC 2500HD CCSB 4x4 Duramax/Allison, Titan 52 gallon fuel tank, Prodigy Controller, B&W Companion Hitch
2010 Jayco Designer 35RLTS, Cummins/Onan RV QG 5500 EVAP, Progressive Industries EMS-PT50C, TST Systems 507 TPMS, RV Flex Armor Roof