73-80 bumper and tuck

[misternash2]

i'm looking at putting a 73-80 rear bumper on my 88 burb. will i need the old brackets to bolt to the bumper? i'm looking at shortening my frame some and moving it in too. i ordered a new 81-up bumper, but the one i have has holes for the pad. a local shop has one for a 73-80 on the shelf. i've heard of guys doing it, but what's it entail?

pics would be much appreciated! i think 72supercheyenne has done the swap, but im having a little trouble finding the right pic of it.