I've never used the Caswell system, but I've done more Kreems than I can remember. I've never done it on a tank where the paint needed to be saved, always either old tanks or new non-painted tanks. I imagine that the process can be done without destroying the paint, but the risk are high. If the acid bath and dryer makes contact with the paint it's like fingernail polish remover. (no I don't wear fingernail polish)
