I crawled around in the dirt yesterday and changed the engine oil and the oil in both diffs (non-locking rear). The oil that came out of the diffs was very thin and black, and there was a good clump of fine metal shavings on each of the magnetic drain plugs. No flakes or other debris, though, just very fine stuff. I'm not sure what the usual interval is, but I doubt the diff oil had ever been changed. Needless to say, there's a lot less gear noise now.
I have the flip-down DVD player mounted on the ceiling, but I'd like to remove it because it just shakes and rattles and I don't have any need for it. What normally mounts up there?