Rockers were on the car when I bought them, took them off as the previous owner had the wrong push rods for the cam and lifters. PR’s are measuring 8.28 not sure if that is totally accurate as I did use a Harbor Freight Micrometer. The hold downs are MP with ARP bolts, they were sanded on when I got the car, I think to make room for the Mr Gasket Chrome Valve Covers that tapered on the ends.