There is some on the hood down side. I will definitely keep an eye on them. Already checked them once after installing new rockers and shafts. Took a press to get the rocker off.
I don't know how long ago that was, but for sure those shafts were loose. The fretting is a dead give away that the shaft wasn't being held tightly in the head and was dancing around. That movement plays hell on parts and could have contributed or been the cause of the initial failure. Did you replace the bolts/hold downs after that failure?