how to remove rear rotor on 2004 Toyota 4Runner

it's loose but won't come all the way off and then the calliper piston came out never seen anything like this

Asked by for the 2004 Toyota 4Runner
To remove the rear brake rotor, remove the wheel, brake caliper guide pins allowing the brake caliper to be removed remove the bake pads and the n the brake caliper mount (secured by two 17mm bolts at the rear of the mount).
Release the hand brake as there is a set of brake shoes inside the brake disc that act on the inner surface of the disc to "hold" the truck when the hand brake is applied).
There are two holes drilled with threads tapped in them near the inner edge of the brake disc near the area the wheel studs protrude through the disc. Screw in two 8mm x 1.25mm threaded bolts and this acts as a puller to remove the disc. Oter the discs are just rusted in place to the hub.
To retract the brake caliper piston, open the brake bleed screw at the caliper and use a C- Clamp or Channel lock pliers to gently retract the piston.