I don't live in the rust belt, so I have no personal experience in dealing with what y'all call "rust", but you need a bolt extractor set:
https://www.walmart.com/ip/Carevas-1...ools/252301773

Note that there's a strong chance the bolt shaft will break and you'll have to drill it out (don't go too deep!) Soak it the day before with some Kroil penetrating oil and maybe you'll get lucky.

Chip H.