Are Brake calipers different between F and M bodies?

[slant6billy]

Ordering Volare Calipers for my 77 and passenger is out of stock. They do have an 80 diplomat in stock for the passenger. Why wouldn't it be listed for the Volare?

Shouldn't it work?

 

[Aspen500]

They are the same for the same years (F and M) but an '80 must be different somehow. Even a '77 vs '80 Volare show different p/n's. It appears that '76-'79 are the same but '80 is different. What changed, no idea.

 

[DCAspen]

Calipers are mounted in a different postion from 77 and 80.Bleeder screw will be in the wrong place if you try to use the 1980 caliper on the 77.