no oil pressure

Well I was wondering what made it break and now I know. The 596 smog head has little passage for the pushrod to go thru like 3/8 hole and the pushrod just spun around and around rubbing on the casting till it broke from just being cut in half.
ever pushrod on that side was scored. The 308 head has a pushrod hole over 1/2 inch none were scored on this head side. The geometry was all wrong to.