The piston should be pushed in as far as it will go and with both pads in the caliper, there should be enough space in between them for the brake rotor. If the piston is all the way in and there's still not enough room for the pads and rotor, I don't know what the problem would be unless they're the wrong pads.when i try to put the pads in the caliper there is not enough space. should the piston be all the way depressed? it will not go down any further??