Wow. It's been a while since an update.
Turned out to be quite a bit more than a rocker seal. It ended up being one of the head gaskets right under the header outlet on the rear cylinder.
Had the bike taken apart for a while, used a seal kit and redid all of them, had the cylinders/pistons cleaned, new rings, cylinders honed and the fine folks at Moto Enthusiasts in Vista, CA helped me out with final assembly and any repairs that needed to be done. I can't thank them enough for their help and expertise with these bikes.
The bike runs like new now and has already been on a few trips through the southwestern states. Look forward to another 60K+ miles on this one.
Pic from a ride not too long ago with my father.
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