[Walt Fricke]

Ordinarily, you don't need a collet to install head studs. Fingers often work. They aren't usually bottomed by the time they are screwed in to the proper height. Which is one reason we are tempted to use a thread locker of some sort.

I don't use the barrel nuts, so I have lots of spares and made a tool from one of them. I drilled a hole across one about in its middle, and stuck a nail through it. Screw it onto the stud until the stud bottoms on the nail, then use a hex socket to do the screwing. When done, the tool should unscrew easily. Quicker than collets or double nutting.

This also allows you to deal with a head stud which had unscrewed itself in an otherwise intact engine.