the sleeves. See if you can pick-up some spare trim-rings from a pioneer installer and dremel them out wide enough so they will fit over the face and slide back onto the HU chassis. Use some epoxy to secure the rings to the metal chassis so they sit just behind the stock radio trim bezel. They will fill the gap inbetween the HU and the bezel cut-outs. That's what I've done on all of my Z installs.