The door surrounds were hammered on Project TJ Reboot, so they had to be replaced. If yours are broken, warped, or cracked too, be sure to let Bestop know these need to be part of your order when purchasing your Supertop NX. If your Jeep still has the molded seals on the belt rail, remove them by pulling up on the plastic rivet. The new door surrounds were installed (drivers side pictured) by inserting the pin in the bottom of the door surround into the hole in the belt rail just aft of the door. Then we pressed the curved channels on top of the door surrounds around the horizontal top section of the sport bar. Four knobs came with the kit. The knobs had threaded steel bolts that were passed through the holes in the channels of the door surrounds, through the sport bar, and then screwed into pre-existing nutserts in the underside of the sport bar.