I think the Darrin has the same stud/nut/washer set-up as the Aero. There is a stud & nut pic posted that is correct, but the rubber grommet/washer with the metal washer impregnated is unobtainium. I have found a great replacement for it, although it includes some stainless steel dress-up. Go to a Nissan Dealership and order part number 16568-77A10. You will find this a good, but non-stock substitute.