Resetting receiver settings after initial setup

I had a hard drive crash on my HD DVR, and was shipped a replacement receiver.  When I was hooking up the new receiver, the initialization was having issues with me telling it was a dual-band, and so I called Support and the agent had me set it as single-band.

Well, now of course we can only record one show OR watch live TV... we can't do like we did before (watch a show and record one, or record two at the same time) - there are two cables back there... how do I get back to the screen to set up the band tuning?