Steering stem fit?

Anyone help.Will a Kat stem fit into an Efe if pressed into a Bandit 12 yoke? I know that sounds like a muddle but I have a spare stem from a Kat and i'm looking at putting Bandit12 forks into a E. I think top yoke will need modifying if I use Bandit 12 top yoke ,is that just to fit the different stem correctly? Otherwise has anyone got a spare Efe stem they want to part with cheap 
