Accord calipers along with most other Honda rear calipers do not push in. You need to spin the caliper piston Clockwise for it to retract and line up the groove so it will slide over the button on the brake pad. There is a special tool to do this but many shops just use a large flat screwdriver (you need to be careful with the screwdriver). When turning the piston, be sure the rubber boot is not sticking or twisting with the piston, you do not want it to tear. Once you've got everything back to together, pump up the pedal before starting the car and verify fluid level. I checked the parking brake after doing my rear brakes and it didn't need any adjustment. hope this helps!