Plug came out after soaking overnight and some more
Can't believe how much pushrod is worn
Both ends were worn hollow, .018" deep on the cam end & .022" on the pump end.
There was major wear on the cam end leaving an effective pushrod length of only 2.874" which is .368" shorter than the MP P529569 pushrod ( 3.242")
I measured the travel of the cam lobe & it measures within 2% of a new Comp cam I have to compare it with so I'm not replacing the cam at this stage, just the pushrod.

Cheers for your ideas.