Thank you, everybody, for your thoughts, especially Kendall. I did investigate a little further. I checked the supercharger fluid level, and that seems fine. The underside of the pulley and snout area is completely dry, as is the waffle-imprinted valley. Once the weather/roads are amenable to GT-travel, I will take the car to my trusted mechanic and have him take a look and listen, and if we determine that what I am hearing is truly concerning, I now know of some good options. Replacing with a take-off supercharger would be simple enough, but I have also been considering a Whipple upgrade. Maybe I will just kill two birds with one stone here. I did the Whipple install on my GT500, and the Kenne Bell boost-a-pump, etc. but maybe for this one I would enlist the help of a Pro like Kendall.