I am trying to replace the rear brake pads on a 2003 Honda Accord. I can seem to make the caliper piston retract enough for both pads to be installed.

I have a large C clamp that I have tried to use, placing the screw end on the piston and the solid on the rear of the caliper. I have the brake fluid cap off

On rear disk brakes, the piston screws in. Try using a large pair of needle nose pliers, or obtain the specialty tool, for the application.

I got the answer myself. But for any other novices like me, here is the answer.

The caliper piston does not squeeze back into the caliper using C clamps or pliers. When you look at the caliper you will see a big bold cross. Using a set of large needle nose pliers, I turned the piston clockwise until it went back into the caliper, giving me enough room to insert the pads.