318 build. what would you do?

i got a axle on the way. im beefin up the *** end. once i get the motor built then ill worry about it. i wanna snap my 7 1/4 before i put a 9 1/4 or 8 1/4 in. im lookin for a 8 3/4 from an a body for my Dart. it doesnt have to be. it could stick out a bunch