Rear Brake Calipers 4&5 lug?
 

Taking a look at my 4 & 5 lug calipers that I have lying around they look exactly the same except for the mount bracket. Are the calipers themselves interchangable? If not what are the differences?.

only on the solid rear rotors is it the same.

The vented rear rotors use a larger caliper than the 4 lug and 5 lug w/ solid rear brake rotors.