Well, took the clutch cover off yesterday, and confirmed that the oil pump gears are the definite culprit. The rear oil pump (the one that pressurizes the oil pressure sender) gear has about half a millimeter of tooth thickness left on the outboard side, everything inboard of that is chewed down to the point where I was able to freewheel the rear oil pump gear. The front oil pump gear was in better shape, but also seemed like it was starting to bevel inboard. I've definitely got something to talk to now, when I give Triumph a call later this morning.
On that note, based on my misfortune, my honest recommendation to everyone that intends do their own clutch change-out is to spend a few extra minutes running a finger over the exposed gear faces of the two oil pump gears; you don't have to remove the clutch basket to get a general feel for how those gears are holding up, and it could potentiall save you a lot of heartache. Best regards to all.
