Tracer Arrow makes the ones that fit a/c/c's - only 3-60's though. If you're shooting anything else you're SOL.

From the looks of the one I've got here in my hand you actually have to remove the uni-bushing that comes in the arrow and then install the portion of the nock that actually contains the light. Then you glue a traditional nock on over that. A bit of a process, and no adjustability once the nock is glued in place, but I believe it's gonna be work the trade off.

http://www.tracerarrow.com is their website.