Wanted to compare the alternator in the S90 with the one in the CM91, and realized that I'd never actually opened up the CM91's alternator cover. There were 2 frozen screws, but they got re-slotted and one whack with the Lisle did the trick.
Stopped short of actually removing the alternator since I have to use the clutch tool to hold it in place so I can turn the bolt.
Worth noting, the CM91's alternator is stamped "CS90". The S90's is stamped "CT90".