I have a chance to buy a decent 2006 CRF450 for $1,000 says he hasn't used it in 5 years, took it to the shop had it service and they said the top end was gone. If I'm breaking into it, I figure I might as well run through the whole motor.. I've never done a full rebuild on a 4 stroke, but doesn't seem like it would be a bad deal with that Wrench Rabbit kit being $699.... Anybody have any advice or opinions? Thanks!