Brake dragging on passenger side,advice/help needed

single piston slider make sure you got the astroglide on the pins. The lip seal is just a (almost) square cut O-ring around the piston inside the piston bore. Im not sure there is a trick on installing these but it may just pop out and slide back in. Check back before you pop it, maybe someone will chime in and tell you the secret of installing caliper piston seals.