First and foremost, thank you all for creating this community. I've enjoyed reading and learning a lot by being directed here on numerous occasions.
I want to ask your advice on cleaning old felt that is just aged and dirty. I recently acquired an early VV-50 portable and the original felt is in good shape, but has years of dust and some light stains. I recall reading that naptha can be used to clean the felt. I'm not sure what tools or technique would be useful to try to revive it.
Here's a photo of the turntable.

Cheers,
PT