I pulled the clutch cover off after draining, to begin inspecting that and uch to my surprise my brand new oil was fill with silver dust, which certainly sucks, but lead me to discover the source of my grinding/whirring noises.
Turns out the teeth on the clutch hub are wearing a bit badly. And at first, I couldn't see why that would be. It's on the drive side, but they meshed correctly?
Then, i noticed that the first pad had worn a VERY hard groove in the fingers of the hub.
This correlates to the short clutch throw, and lack of disengagement I was seeing before teardown, and also can point to the fact that if that first plate was locked in place, moving the clutch depressor might be pushing and pulling the bell against the primary gear, causing this wear.
Looking for opinions on this, as I have never had a shifter wear out a clutch hub like this. Not sure if removing material to resurface the fingers is an option, or if that will cause too much slack in the pads.