Interesting that - I actually wimped out & had a chat with my local indy yesterday (that looks after our other cars) after sheeting another stud. I took the driveshafts out of the Zero & dropped them in. They did basically the same as you - they reamed the holes out a little, then pushed the studs through with their 25tonne press (& apparently blew a seal on that!).
Pardon my naivety, but in your example above, does that mean that 8 turns (12/1.5) is the minimum number of turns required for engagement?
While they were doing the studs, they also noticed that once of the wheel bearings isn't running very smooth so guess what's just been added to the job's list!