He's only 2 months old? You can probably switch him pretty easy. I switch them over by feeding smaller two prey items per meal, one right after the other. Like this guy, he can easily eat two hopper mice in a row... and they tend to be less picky about the 2nd item than they are about the first. So feed him a hopper, then follow with a rat fuzzy. If he takes it, you can try leading with a rat fuzzy next time.
ps. is he eating f/t or live?