The SWM kit is installed on the roof beside the antenna and some hardware is added inside the coach. Here is a guide for setting up SWM.
http://www.winegard.com/kbase/upload/2452242.pdfYou can order the SWM hardware directly from Winegard Customer Service at 800-288-8094.
Despite the assumption that the DirecTV installer knew better, it's much more likely that he did not have any idea that what he was doing would have any effect on the use of your receiver in your RV. Remember that nothing you have installed on your RV was built by DirecTV but rather is a creation of the RV market. DTV does not know (and will not concern themselves with) RV's or their equipment. It's the RV industry that must make the adjustments to the satellite industry changes. The SWM kit addresses that for existing customers and Winegard will likely address the future direction of DirecTV systems going forward.
Let us know if you need anything else.