Badly worn rocker arm shaft

So, I've been working on my Dauntless V6 conversion and found one badly worn rocker arm shaft. Some of the rockers show excess wear, but the shaft is really worn down. What do you think is causing the shaft wear? I've placed an add in the classifieds for a rocker assembly.

 

Best guess would be lack of lubrication as in plugged oil holes in head or shaft.

 

There was a lot of sludge in the shaft when I cleaned it. Maybe enough to starve the oil supply???

 

It is possible to install these shafts backwards which restricts the proper oil passage. I have seen it more than once.

 

One side is not used IIRC. On mine it was packed solid.

 

It is possible to install the shaft upside down, with the oil galley up instead of down, but that was not my case.

 

Not sure what you mean by "one side is not used".

 

In the head, there is an oil passage that is not used. It is covered by the rocker arm assembly IIRC. That passage gets filled with ick. The oiling system for the rocker arms is not great on these engines.