Clearances are all good, this is the result of way too far advanced timing. Haven't decided whether Im gonna split the cases yet, but the crankshaft, rods, and cylinder head are all undamaged. Found a little metal in sump plug screen, and main oil filter, flushed engine thoroughly, trying to decide whether to split the case or not. Got new Pistons and rings (thanks Lowell), cylinder was saved by a hone job for $20 (thanks to Will's machine shop). $140 worth of damage, ready to go back together with her...
