Okay,
this Model M 1391401 is on eBay:
The 1391401 is
the typical Model M, and everything about this one is what you'd expect—except this:
Excuse me—
ExSel instead of
Esc? What does it mean? And why is this on a '401, when IBM was so crazy fond of creating new p/n's for even the most minor variations?
I'm thinking maybe this board did originally have an
Esc, but the cap got lost and someone substituted
ExSel from a terminal M. (I can't say for sure I've seen
ExSel on a terminal M, but it seems like one of those terminal-style legends, doesn't it?)
Whaddaya think? I know this is the sort of thing that delights you guys, and I wouldn't want to deny you any excitement, cap-wise.