I have the early a-body disc brakes on my Demon, I was bleeding the brakes and I didnt have a rotor on one side and a piston came out too far and fluid came out, I used a C clamp to push it back in the leak stopped but I see the rubber boot has come halfway off, anyone know how to slip it back on.thanks

You will probably have to remove the piston and seat the dust cover back into its groove. then re install the piston . I wouldnt force the piston it should push back in by hand, forcing it could cut the o ring and cause a leak.

Thanks , does the piston come out by taking the caliper apart or can I just pull it out the front, I appeciate the help

The pistons come out the way that one came out. If the calipers are old I would put kits in them. The later calipers have to have the piston out to get the dust boot installed correctly. The early (65-67ish) had a different boot style that could be put on with the pistons installed.