The satellite prewire (coax and data cable) are near the center of the coach roof (side to side). You can identify the location by finding a white blank wall plate near the center of the bedroom ceiling. Pull the plate off to reveal the cables.
Terry H just installed a Trav'ler on his new coach. He carefully read the instructions and noted that a clear radius of x inches needs to exist around the dish turret. Based on the radius required, he elected to mount his dish ahead of the front AC unit. He told me the data cable was long enough to reach his dish.
On my current coach and the 2 prior to it, my Trav'ler dish is mounted behind the front AC unit. Behind the AC unit leaves the Trav'ler a bit more protected from tree limbs and such. But it may not fully meet the clear radius requirement of the dish, though I've had no interference issues with mine.