Just to clarify:
1. I'm doing this with head on the engine, in the car.
2. The studs are the e-bock kit which are the ARP studs/nuts/washers.
3. The stud must have un-screwed when rocker assy was removed and I didn,t catch it on re-assembly.
4. This hole is the oiling hole, which is chamfered and has restrictor in
oil hole.
5. The helicoil which pulled out was the original put in by E-brock, not a repair.
6. The coil pulled out cleanly taking only the alum thread matl, leaving a 1/2" hole which might just need to be tapped for a timesert. If I need to go bigger to a "bigsert", then i"ll have to drill.