Good for you, I hope the solution works.
Did you note how much torque was applied?
When the acorn nut was bottoming out, the reasionprobably was
the stud was already pulling. Did you reinstall the acorn nut or
are you just reluing on sealant? If you need more clearance so
the acorn nut doesn’t bottom, a good solution is a thicker
washer for the O-ring. The limit there is clearance to the oil
cooler.
Whan a mag-case cylinder stud starts to pull, the first clue usually
is the 10 mm Alllen wernch no longer fulley engages the hex in
the nut.
With your custom stud, the 8 mm diameter in the area of the oil
passage (red arrow) is necessary. There needs to be suficent
clearance for the oil to get past the stud and feed the #1 main
bearing and the rod bearings.
I know you realized this but I didn’t want someone in the future
to install a completely 11 mm OD stud.
Best,
Grady