Latest update. I'd been noticing some clatter in the top end and recalled that the timing chain tensioner was fully extended when I pulled it apart. Well my chain is stretched out enough to slap the side if the case.. What was making it worse is I installed the front timing chain guide incorrectly.. The installation instructions in the service manual were everyone's favorite "installation is the reverse of removal". When I'd removed it I'd just lifted it out of the crankcase, when I put it back in I just dropped it in in a way that 'felt right'.. Now that I have the crankcase cover/flywheel/starter gears off its abundantly clear that I didn't install it right and it got chewed up, so I've got new timing chain and guides otw. On the bright side when I drained the oil this time it came out clean with no visible metal pieces, so maybe I'm still headed in the right direction.