If you are installing the OEM ski doo replacement grip, you will need to feed the wires through the plastic tubing down to the connector block. You might not need to remove the switch housing, and the throttle block doesnt come off w/o the grip out of the way, so no need to try. The inside of the throttle housing has a plate that comes off with a small screw behind the throttle cable. To remove grips, if they don't rotate and pull off, just use a sharp utilty knife to cut along the length of it, it will split open and come right off. You will have to push pretty hard w/ the blade to cut through the hard plastic liner inside the grip. The new grip may have to be "pursuaded" to go on with a block of wood and hammer. Should'nt take a lot, just a few taps to seat it in position.