Toobless Goo

I'm tired of answering questions around here. (At least the ones I have answers for.) And now I want answers dammit! I've been using Stan's tire sealant for years now. As a non pro racer, I'm not constantly changing my tires and use enough air pressure that I don't flat often and never burp out air, so I don't usually break the tubeless seal before the sealant has gone dry. So when it's time for fresh tires, or in this case NOS grey Michelins that I got on sale and have been sitting on for years, I'm stuck with a bunch of dried up Stan's inside my rims. Do any of you have a method to get the stuff off other than friction? Soap and water? Rubbing alcohol? Fire?