Mike,
I do not know the answer to what drive I used, but can check on it for you. May be a week or so, until I can over to the coach. I have so many HDD's laying around. I just popped one into a USB HDD case and plugged it in without really thinking about it. Actually, this was a tip a local installer told me about. Since I pay for DVR service at the house anyway, it made sense. To be honest, other that seeing the IRD recognize the HDD properly, I didn't spend much time testing it out.
Regarding the signal to the rear of the coach, our PT had coax running to the rear and the basement already. It also had a coax push button "swtich box" already installed that facilitated the switching of "VCR" "ANT" and "AUX" to the front or rear TV's. I don't need this at all for the front HDTV anymore, since that is all HDMI switched from my Yamaha receiver, so I now relabled "front" to basement and can switch the signals to basement and rear TV using this existing switch.
I have a spitter for the OTA (digital off-air) that divides the incoming antenna to 1) the new HDTV and 2) the Satellite IRD. The IRD has a coax output which is connected to the switch box as antenna in. So when I want to watch Satellite or OTA in the rear or basement, I simply select it at the switch box and that signal is sent to the appropriate area.
To make things even more useable (complicated) I have a video modulator hooked to the front BluRay player as well. This converts video/audio to RF. This RF signal is connected to that same swtich box as "AUX" input. So I can send the bluray signals to the rear or basement as well as the satellite and OTA signals. One caveot however is that the quality is not HD quality at rear TV. Only SD over the existing coax at this time.
This only works, because I still have the old Sony TV in the back. Once, I upgrade it, then all this RF will need to be re-addressed. I have seen a few HD over coax devices, but have not experimented with them as of yet.
Hope that helps
Jim