Nice thread...kinda crazy all the parallels between this build and the one I'm doing for my son. I bought a '99 KX60 with a rotten crank and trashed top-end back in September '09.
Working two jobs I haven't had much time to devote to the KX60 project. Over several months I've managed to recover the seat, yank the engine, clean up the roller pretty well, and install a new rear knobby. I have big plans for the original engine, but in the meantime I decided to bite the bullet and get my son an engine off of eBay (seller has over 200 feedback, all positive, and he says that the engine was rebuilt from the crank out). I really wanted to have the bike ready to ride when my son got back from church camp, unfortunately the engine has yet to arrive. Worse yet, the seller hasn't answered any of my messages in over a week. So the bike may have to wait for the 70.65cc big bore I'm building out of the original engine.