Main studs or conn rod bolts? All the sets i’ve ever worked with had no marKings on the studs besides ARP. On the rod bolts, that’s a diff story. I’ve had them marked 2000 for that series. 8740 for those. I’ve had arp eagle 8740 on eagle rods etc.. main studs, i’ve never seen them marked with the grading.

1.50 60Ft. , 10.75@ 127MPH Hauling 3900 LBS.