70-73 swinger rear bumper/quarter extension swap

I have recentley purchased a california '73 dart/swinger body shell,and have begun with a BC canada 73 car(rust).I dont like the 73 nose so i've been collecting 70 nose,doors,dash,etc.Figured I'd better change the rear of the car to match the front.I'm pretty sure the nose swap will be pretty easy,however,i am concerned about the quarter extensions and rear bumper being a bolton.Does anybody know if there were any bolt pattern changes between 70-73 for the rear bumper & quarter extensions?
Any imput appreciated,thanks.
Author: admin