Well the problems keep arising !!! ran into another one today, heads are now all torqued down and I wanted to address the rocker fouling issue but after stripping the shafts down I found the base of the shaft assembly was fouling the head studs !!! I think whats happened here is it was made for an engine with head bolts as there small recesses for the bolt heads to go into, as i'm using ARP studs which use a parallel washer and a thicker nut the recess needed to be bigger all round.
Anyway an hour on the mill sorted it all out and they both sit down nice now.

I started by doing a single pass with a 5/8" cutter but it wasn't enough









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