I think the first kb I ever took apart was a Model M, but that was years after I started using computers. I used to help my dad fix computers at work on the weekends, so he could get overtime. One of the things I would do is clean the keyboards of negligent users. We would disassemble the 'boards and soak the appropriate parts in Simple Green, then wipe them off and put them back together. Until then, I had no need to take one apart, but I was pretty young back then, so I was not as curious about how things worked yet.