OK, I've got these '02-era (OEM for Trek 800) Gripshifters -- I'm replacing the cable on the right one, but as I was putting in the new cable, I knocked out the small v-shaped plastic spring/ratchet tooth. Where do I put it back? I've uploaded a lot of photos to: http://tinypic.com/a/wxvo/2
You can see the full high-res versions by clicking through to the "view raw image" level.
There is a space on the shoulder of the inner part of the shifter a bit wider than the arms of the V, and the bump on the middle of the V goes onto the detents on the outer part for the number of gears.
I had to look those up. I have honestly never seen those shifters before, and I was a bike mechanic back then, too. I guess it's because we didn't sell any bikes that inexpensive. (The shop I worked for then started with MTBs at $300)