I am getting confusing and conflicting advice from Dish. I am a novice, so please bear with me. I have a total of 5 receivers. An 811, a 921, and three standard receivers. I have a "500 Quad" switch and a SW-64 switch. I have two dishes (dish 500?). The 811, one standard receiver, and the 921(2 lines) are on one dish connected to the 500 Quad switch. The remaining two receivers are on a seperate dish connected to the SW-64 switch. My question: What is the easiest most cost effective way to add a second 921 to my system, and what equipment would I require to do it? Any guidance would be greatly appreciated.