So just finger tighten the studs to the engine block and then torque nuts to 15 ft/lbs?
I just remember when I was rebuilding my car engine, we had torque specs for both the studs to block and the head stud nuts
The thing is, since they’re just studs, the tighter you make them they’re just going to be bottoming out in the hole which could make them break through the inside of the case, or they’ll be bottoming out where the threads on the stud end. A normal fastener has a head that it bottoms out on giving it the proper stretch to the threads.
If I remember correctly, I believe MRieck installs studs with red lock tight to something like 5 lb ft. But he slides the cylinders and head over the studs and puts the nuts on snug just to align the studs to the holes in the cylinders and head. Otherwise they could be cocked a bit. He leaves it to cure overnight.
That being said, you don’t need to replace the studs unless you have to.