The Master Cylinder (3/9/2014)
I believe those are part of an external oiling kit. A copper tube was routed to one of the studs which was hollow. The oil then flowed through the "machined slot" in the cap to the hole where the overflow tube used to reside to pressurize the rocker shaft.
Hope that kinda makes sense...
Ah-ha, that explains it, there are two studs that have internal allen hex.
Thanks, the Master
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