i know this post is old but if anyone was curious i rebuilt the top end. went 60 over stock and went to fire it up for the first heat cycle and still had the crazy grinding scraping noise. so i started thinkin bottom end needs rebuilt. crank or connecting rod bad or bad bearings. i took off the cover for the flywheel to see if i could move the flywheel up and down to see if crank bearing was bad but the damn flywheel fell off into my hand. SHEARED THE DAMN WOODRUFF KEY again. i dont have the tool to tighted the flywheel properly. before i used a shirt and jammed it in there until it wouldnt spin anymore and tighten it down. im buying the tool tommorrow and starting it up!