I got a 1yr old Bumblee Bee that was only ever fed Live.. I wanted to get him over to F/T as quickly as possible..
I put him in a feeding tub, danced the F/T rat around w/ zero interest. So I placed the rat inside the tub, put the lid on, turned off the lights and went back an hour later and checked on him, and unfortunately the rat was still there..

Gave it a few days, and tried again.. turned off the lights, and left the F/T rat in there.. came back an hour later and he had eaten the rat! Now all he eats is F/T each time!
Give this a shot and see if it works.. I've tried this method now with a few that i've switched over, and for me, it's worked each time.. Except with one.. who just wont take F/T .. sometimes Live is the only way!