Hi,
You mention sometimes wanting the simplified nitty gritty so to speak, so here's a page I put together on thru-hulls:
http://home.comcast.net/~ericson-yachts/thull/thull.html
There are a lot of slight variations on the theme, but this should get you in the right direction.
Some more thoughts. Don't get lulled into thinking the bronze on the boat is in good shape. Replace it all. I say this from the experience of having replaced everything but the actual thru-hull (this was on a '66 Columbia 24 I had years back), and went to wiggle a new drain line on the new barb on the new ball valve, and the whole thing broke off between the ball valve and the hull. I was supposed to launch the next morning, and was very happy I didn't save hooking up the sink drain line until after launch.
This brings up something else. Thru-hull fittings and seacocks are straight thread, but ball valves are NPT - a tapered thread. Beyond not providing a solid valve to hull joint like a seacock threaded down on to the backing pad, they don't thread properly.
I like using a good quality pipe dope instead of teflon tape on the threads. Coat both sides of the backing pads as well as the thru-hull with your adhesive/sealant. For bronze, I've had good luck with 5200 Fast Cure. For plastic, I use the 4200 Fast Cure. When you tighten down, hold the thru-hull and turn the seacock. If you spin the thru-hull, you'll spin out too much sealant. The old timers who guided me on my first thru-hulls prefered to tighten up nice and snug and leaving alone. Many others like a technique of partial tightening, then waiting for the product to cure, and then final tightening - the idea you leave more material being squished as a gasket. I've always done a nice and snug torque with large wrenches and left them alone, and have not had any issues.
While you are at it, check out things like your knotmeter sending unit. I had a core disintigrate on me when I pulled it out of the housing - it was being held together by the compression of being in the thru-hull fitting. Pretty scarry to think I sailed a season like that.
Good luck, and keep us posted.
-David
Independence 31
Emerald