will 70-72 bumpers bolt to a 73?

The bumper should bolt right up, the bolt hole pattern on the frame stayed the same until around mid '74 when the 5mph bumpers became came out.
are the shock bumper the 5 mph bumpers? my 74' swinger was fist sold 10/25/73 and has them. guess it could be crappy "i'm your mother damn it" california crap... :dontknow: