If you are going to paint it then, you can get it sand blasted. That will get a fair bit of it off and if its really crappy and peeling it might just blow off real easy when the sand blaster does it. It depends on how good/bad the chrome is. I dont mean glass beads, they wont touch it, its gotta be the coarse sand. You need to make an assesment as to how much rust is around the place and if its really under the chrome or not. To be on the safe side i think iwould take it to a chromer to chemically strip so that all the chrome is removed and there is no patches left on it that may still have rust underneath. After chrome striping i still think you will want to get the frame sand blasted anyway because whenever i get stuff stripped for dent repairs etc eg tanks, they rust really quick after the 'pickling' process and they would be no way near ready for painting. So yeah my addvice would be get the chrome stripped chemically first, then do your frame repairs (if any) then get it sand blasted. That would be the best way to do it.