I had my 27 inch monitor on a stack of books for a year. My neck always hurt after 3 hours of work. Last week, a friend saw my setup and said, 'Your screen is way too low, you're looking down all day.' I measured it, and the top of the screen was 4 inches below my eye level. I bought a basic arm mount for $40 and set it so the top third of the screen is at eye height. The neck pain is already gone. What's a good rule for checking your own monitor position?
Yeah, the "old truck seat" is a great example. It makes me wonder what other everyday things teach us good posture without us realizing. @patricia385, did you find any other weird tricks like that before you learned the eye level rule?
That "top third at eye level" rule is the real deal. It works because it keeps your head in a neutral spot. I should have tried it years ago instead of just dealing with the pain.