Yoshiyamaha68

I have a 86 js550 stock engine.. no pipe, the only thing i have done is a k&n filter... i recently bought a 44mm mikuni carb for it.. it does have the round fuel pump.. i have read some threads saying that it will hit the head of the engine.. but i have also read that 87 ski's come with a 44mm carb stock.. The real question is will this carb work with my ski... if it hits the head can i buy a intake spacer and make it work.. i cant find any answers to this with another thread.. so if i need to do some jetting or buy an adapter or if it will just plain out not work ...if you could give me some advice that would be great.. thanks..