This is good. Thanks for the advice. I've gotten the tap (and a spare), and hope to get to this stage of the project in a few days. Will report back afterwards.

Now, the tap has a funny square end on it... think Vice Grips will hold it?

Hehe, hope you were joking. Use tap handle only.

Yeah, I was joking. That's about as good a joke as I'm capable of telling.

Family thing has come up, and I'm going to have to leave town. This delays installing my bolsters, but I will report back afterwards. Thanks again, all.

Why don't you just through bolt them? You'll just need one of those 6' long drill bits the electricans use.

Jeez Cord, I thought you were brighter than that. My boat is a deep v, and there is no good way to get either the head of the bolt or the nut to torque down correctly if it's not perpendicular to the surface it's compressing, which would be the bottom of my hull in this case. You guys with cats don't understand what it's like.

Besides, where would I find a 1/4-20X24" stainless steel bolt?