77' Vette Rear Window.. Help????

What's up guys??? My dad and I just purchased a 77 White Custom Build 350 386HP 422TQ

BUT it was repainted a few years ago (the same color).... And wasn't the best paint job so they ended up over spraying a little on the "gasket" for the rear window... This stuff is like nothing I've ever seen before.. It's rock solid and seems to be some type of weird epoxy.. Few people we've talked too stated this is normal and is not like the gaskets used on the t-tops, doors etc...

So anyway how can we get the paint off w/o messing up the paint??? OR how can we get the stripping out of there so we can replace it? It's not leaking so there really isn't a reason to take it out but the over spray makes the car look cheap because it's not fully white but rather spotted in areas... Could we sand it? Get a really sharp knife and try to cut it? I would have no problem bringing it to someone who's done one before and have them replace it BUT the guys are Wayne, NJ haven't done a 77 Vette yet... All the mechanics and body shops haven't either.... Wouldn't mind paying a $100 or $200+ and having it replaced but it's not looking good.. Sorry for the rambling but I've searched and searched and it seems the only discussion are regarding the t-tops and door weather stripping and not the rear door...

Please Help????

Thanks!
Bry H

Fine steel wool dipped in Trans-X.