Couple rearend swap questions/brakes etc

[**grumpy**]

I have a 72 12-bolt 3.08 rear to swap into my 66 short fleet.
I know the 72 is 3/4" wider on each side, which is fine.

I dont have any backing plates or brakes on the 72 rear. Will the backing plates and brakes work from the 66 rear?

Also, I ordered a bolt-in cnotch from cpp, and their super trac-bar. I was going to order the 1 1/2 or 2" drop block/ubolt kit, but 70 bucks plus shp seems extreme.
I can make steel blocks for zero, and just need Ubolts. So anyone know where to buy reasonable Ubolts, or can anyone give me measurements so I can have them made local??

Thanks fella's