Brakes and calipers (please help!)

I have a P Voyager 1993 with a 6 cylinder and 15" wheels. The brakes started to go. So I decided to do a routine brake job. So I have the rotor off and the caliper off and it seems the piston will not go back in place. My C-clamp handle bent so I know it's not budging. So I think I'm going to have to replace the caliper. I've removed the resivoir caps on the master cyliner did I possibly miss something? I know that my questions may sound stupid but sometimes it's the little things that get in the way. Pleae feel free to mention so of the obvious.

I'm very new to auto repair this goes beyond my experience level. But there is no turning back now it's all apart in my drive way. It seems that The caliper is connected by one bolt. (connecting the brake line) However I know when it comes to the brake line and fluid it's probrably going to be difficult. So if at all possible could some one walk me through this process. How do you plug the line when swapping the caliper? and are there other things I should watch for? Any advise would be greatly appreciated.

Thanks in advance!
:banghead:

Do you have a repair manual? They generally cost about twenty dollars. Many '90s and newer vehicles have special procedures and need special tools (the tools aren't expensive and maybe available for loan at autoparts stores) for compressing brake pistons. If this vehicle was a Ford, you would need replacement calipers because attempting to use a c-clamp ruins them and possibly some hydraulic parts when moving fluid in a reverse direction.

The caliper was only $15 at auto zone. I just swapped it out and it seems to be fine. Thanks for the help.