Duster 73 bumper brackets same as 72?

So was super lucky and scored a 73 duster rear bumper and rear plastic sail planes that will go on to my 74, it doesn't have any brackets. I am guessing its 73 as has the jack slots. She is rough but will have it re chromed as shipping a new bumper to Australia be a fortune.
So the question is are 72 brackets the same as 73. As on YearOne they say brackets 71-72.
Yes i know i need to make a few adjustments to the rear of car to get it to tuck as i had the 5mph brackets