I have had the great fortune of picking up an owned HR24-500. I'm debating upgrading the internal drive to a 2TB WD20EADS myself. Not sure what I'm getting myself into however. Anybody have any instructional tips on how this thing comes apart and what tools you need to have handy? Is there a schematic or service manual anywhere out there? It certainly doesn't look as straightforward as an HR20. Or maybe I should not even bother and just add it externally.