[mcbeevee]

After further reading, it appears that with a SWM dish and 4 way splitter, I could use one cable run into the house from the dish and feed both tuners on both of my existing DVR's. Is that correct?

Yes, with SWM, you only have 1 cable from the dish. This cable can use green-label splitters for up to 8 tuners (16 tuners with a SWM16). In your case, you could have 1 cable from the dish to the living room which feeds a 2-way splitter. The 2-way splitter would feed 1 cable to each DVR (SWM DVR's only need 1 input cable, but still have 2 tuners).