Rear Bumper Sill Bracket Heights

[Highwaz1]

I have an early 1030 Tudor. A previous owner destroyed the rear bumper brackets and I see a couple sets for sale on eBay.

The brackets that connect the bumper brackets to the sill come in 3", 4.5" & 5". It appears that I need the 4.5" for my Tudor.

My question is whether the bumper brackets are all the same with different height sill brackets used for the various cars OR if the bumper brackets are different in addition to the different sill brackets.

For example, can I buy a used set of bumper brackets that have 3" sill brackets and then change out to the 4.5" sill brackets and have the correct configuration? Thank you for the help.