More progress today. Went to work with the wire wheel and de-rusted the frame, it was actually a lot better than it looked at first:
I painted too, but I used a light gray paint that is almost exactly the same color as the primer, so I didn't take another picture. I have a few free hours this weekend, so hopefully more progress will be made. The new parts are starting to trickle in via UPS, which is good since I don't have much more to do as far as re-finishing - gotta start reassembly after that and I need parts to do so.
Basically the only thing I'm not sure on as far as parts matching up is my wheels and brakes. I'm 95% sure the 17" wheel I ordered will fit, but won't know for certain 'til it gets here and I do a test fit - if it doesn't I'm in trouble because the stock wheel is a ridiculous 15". I know the front wheel I want will physically fit the XL600R axle, but I'm kind of taking a shot in the dark as far as getting the brake caliper in the proper position, it might require a custom-made bracket. Not a huge deal.
The biggest unknown is finding a decent-sized tank that fits close enough to work. I have a few to try, hopefully one is at least close enough to "massage" into the proper shape with a hammer.