Unfasten the bottom bolt ,lift the caliper up ( Its on a spring and hinge ) remove the pads . Screw the piston clockwise until it bottoms out , then lower the caliper and reinstall the lower bolt.
I need a daigram of the rear brakes being changed
front or rear
Are you asking how to??
You will need the tool to retract the calipers. The piston in the rear calipers have to be turned clockwise as you compress them back in.
Get some one else to do it
disc brakes - front and rear
Depend on what year cadillac you are talking about, and what model.
i need a diagram on how rear brakes are assembled
Check out the related video on how to change the rear brakes on a Saturn.
drum brakes
Conventional drum brakes.
Assuming you mean rear disc BRAKES, yes.