SMEDEN, you were the closest! Once I got Goldie back home in my garage, just BEFORE engine removal began, I whipped out the mechanic's stethoscope... back on the centerstand, running in all the gears at different speeds I was hearing awful things coming from the swingarm...pulled back the u-joint rubber boot, & shazaam, there's the problem: the snap ring had popped off the end of the driveshaft at the u-joint...allowing the drive shaft to drift unsecured in the swingarm an inch or so, trying to drill it's way out of the swingarm! Found the distorted snap ring lying in the bottom of the u joint boot, repaired & reinstalled it (new spare snap rings are on the way!)..and now the driveshaft, engine & tranny are quiet & happy once again...BUT WAIT, THERE'S MORE ! Took her for a test ride, and still is a horrible noise coming from the front wheel (Bearing Failure!). Turns out, the 'spare' front wheel I had recently installed has the wrong speedometer drive hub on it (that part came from eBay from unknown donor bike, looked correct to me, no, it's a few mm thicker than my OE hub). That wrong part threw off the geometry of the axle & new bearings & brake caliper holders...what a mess now! So I reinstalled my OE front wheel with correct axle & speedo hub..ALL IS GOOD NOW!!please make sure that your problem does not originate from the drive shaft or final drive gear / wheel flange before disassembling the engine.
I know several who have found the fault there, AFTER they had disassembled the engine
The snap ring failure was my fault...I had recently rebuilt the driveshaft with a BRAND NEW U JOINT (Moog #405)...I was so proud of myself for finally achieving this long sought goal that I skimped (reused) the old snap rings...Rookie Mistake! And the front speedo hub mis-match causing bearings to revolt in misalignment...Senior Moment! This cross country trip was doomed from the start..and I've got a 'new' unnecessary spare motor arriving tomorrow (yeah, the wife is thrilled) At least I figured out all this sh*t before I tore Goldie down into much smaller pieces...thanx y'all for your suggestions!