Mouse poop mayhem!

I want to keep dad’s T as original as possible. One of the cool things about it is it’s period seat covers protecting the original upholstery.
The front seat covers are near perfect, but the back seat was loaded with mouse poop.
This morning I shop vac’ed it up however I suspect there isn’t going to be way to sanitize the seat covers.
I have no way of knowing if these were original to 1924, but judging from the tacks holding the fabric on(a bit of rust on the tack heads) and the excellent condition of the upholstery under the front seat covers (I took a peek) they could have been installed by the Dealer, Althouse-Eagle Co., in Stockton, CA, in 1924, but I’m certainly no expert!
Anyway I figure they’re worth preserving if possible. The bigger issue I see is if the seat covers protected the original upholstery underneath from mouse juice. If so I could look for matching seat cover fabric and find a shop that could tack on new covers. If not then re-upholstery might be what’s needed.
My question is how to proceed? Is there a product to sanitize seat covers?
Should I pull off the seat covers to inspect what’s underneath? This is very old fabric and likely will tear much of it while pulling the tacks.
Thanks for any suggestions.

Maybe take the seat cushions to the car wash and hose them down?

Can I do that with mohair?
I think the original upholstery is mohair.
I’ll have to look that up.

Maybe there is some kind of dry cleaning product I can use?