4:3 to 16:9 conversion

Hello. My first post here, seems like a great forum. My question is, can you convert 4:3 to 16:9 in FCP. You see, all my video in in 16:9, but i would like to add to it with a helmet cam. As far as i can tell, the helmet cam can only record in 4:3 on the Sony camcorders. What would be the best meathod to cut this together and maintain the ultra-cool 16:9 look?
Thanx!
Adventman...