While Montana does not publish electrical wiring diagrams for their RVs, contrary to what others believe, they do publish the TV and Satellite wiring diagrams. AFAIK every Montana has the identical TV and Satellite wiring configuration. The diagrams have been posted numerous times. Prior to 2010 they used one setup, and subsequent to 1/18/2010 they used a better one (isolated satellite cables). There has been so many requests for the diagrams that John Kohl had them stored as a "sticky" in the Topic "Sticky: "Did You Know" and How to INDEX"
A direct link to the diagrams is here:
http://www.montanaowners.com/forums/...ad.php?t=37324
I can't help answer any of your Winegard questions but I can tell you the Satellite cables in the current Montanas are devoid of splitters or other interfering devices. Each run goes directly from the convenience center to the connection plate in either the entertainment center or the bedroom closet. There is no need to run a new dedicated circuit. Use the ones provided.