[dmford]

Still trying to find out if I have a H.O. I borrowed a scope and looked at the top on the piston. There is a fish-eye lens type of distortion but the piston does has a concentric ledge approximately 1/3 of the radius away from the cylinder wall. Is this the valve relief? is it probably a H.O piston? It also has a small ~1 " diameter circle in the center of the piston.

Dave