Mark,
Most things here come through GoFasters. My '07 came with just a plate, I have a Hebo Granada light from an '05.
This was discussed a few months ago I beleive in another thread, maybe even some dimmensions listed there. I know a Husky rear wheel is not going to fit right on, but I can't say its impossible either with some custom parts. KX rears will fit with a spacer change I beleive. I've also heard it done with KTM rears. If the rotor to sprocket dimmension is the same, the offsets can be corrected with custom spacers.
What I do know first hand, as I've just done it, is that a pre '04 front wheel set up for the 20mm axel used with WP forks can be eaisly converted for use on all the new bikes with the 25mm axel. You need to swap the bearings, seals, center spacer, and two wheel spacers. The hubs have different part#s, but all it seems to be from my measurements is that the newer hub is cut 3mm more narrow on each side of the center casting, as the newer bearings are more narrow. The thrust or load dimmension across the bearings and spacers inside is exactly the same. All this does is cause the seal to ride 3mm more outboard on the spacers when seated flush, which is perfectly fine.
A pre '03 rear wheel goes right on using its own spacers, axels are the same.