I ran across the Otto Service web page some months ago. I found it to be informative, and spent quite a bit of time wandering from page to page. Here's a couple of links to get started on:

Jack Basics
Floor Jacks Background


Joe
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'67 Chevy C20 fleetside, 250 inline, 3 on tree, heavy duty clutch and brakes, heater, steel bed floor
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"Tighten until the stud snaps, then back off half a turn."