I am going to change my rear and front brakes on my 05 C sportster. I need to take some brake fluid out and push the pad in so the piston goes back in the calipers so I can remove the pads. I was told to PRESS IN the round circle that says HD on it and it is located on the side of the caliper. That doesn't sound right to press it in to somehow make the piston goes in. Will this work I don't want to try to do this if this is impossible Any help to do this will help