Topic: Rear Brake Backing Plates - 66 Dearborn A code GT

[Jondors]

I have two sets of backing plates.  One set came off my Dearborn GT Fastback built in Dec 1965 and I’ve lost track as to which set goes with the car. 
I’ve only found conflicting information on backing plates.  I will be installing the original 8” rear end back into the car.
 
First question, should a 1966 Dearborn built Fastback have 2” or 1-3/4” rear brakes?
 
Second question, of the four backing plates I have, which ones are correct for my car (if any).  I’ve read where some cars had a mix of KH and Bendix on the same rear end.

These are the Part no.s on the backing plates I have.

71085 KH - Kelsey Hayes
70867 KH - Kelsey Hayes

313355-L – Bendix
313356-R - Bendix