The timing of this thread was too coincidental to pass up! Just two weeks ago I spent the entire weekend rewiring my house. By doing so I was able to drop a 301 off my acct to save $5/mo. But the REAL reason is that since I have 2 510's, the wife and I are getting frustrated with the separation of the 510 hard drives. You dual-tuner DVR owners have it nice! I know I could lease a 522, and save $10 by doing so, but I'm kinda waiting to see what Dish is doing w/ MPEG4 before I get yet ANOTHER new receiver from them. So, without having to spend ANY money, the diagram represents my new setup.
I remembered a program I used to use called Smart Draw, and downloaded a trial copy of the current version to help make sense of it all. Ended up making and/or borrowing the images, instead of using the TONS of images that came with that program. By the way, Smart Draw is a very powerful tool!
Before you look at the diagram, I have to say that the setup does in fact work! Need to do something about a couple of the splitter-fed TV's though, a little grainy, but I'll work on that another day!