I asked him already. IIRC, The backside of his wheels are not flush - there is/are recesses. The ends of the lugs tuck into the recesses in the wheels.
Depends on which way you want to go. They make some like above. Or they have some that you use longer wheel studs and the spacers go over them. We went that route on a buddy's SVO when we used the Bullitt wheels. We used a 7/16 spacer and longer wheel studs from Summit. I think the lugs are 1/2 x 20.