l bought the standard brake caliper tool to compress it but it will not go all the way back in
please help trying to get this done tonight or l will not be able to go to work tomorrow

http://autozone.com/az/cds/en_us/0900823d/80/05/13/56/0900823d80051356/repairInfoPages.htm

they turn in. if its too rusty you might have to replace

the piston goes in with a special tool that pushes and turns them in. l have used a c-clamp to push the piston while turning clockwise with the vise grips. It is common for these calipers to freeze up.

If the piston is not moving with the tool it is frozen and you need to replace the caliper. You can try uging a small piece of wood and a C-Clamp instead, but do not apply more pressure than feels right because if it wo not move it is not going to. Best of luck.