I just finished binding the fingerboard on a Rickenbacker guitar from the 1960'S and decided the truss rod needed adjusting. The nuts were almost stripped, but I got my wrench on one of them and decided to loosen it. It broke off! Dang! What I want to know is can I replace the rod without removing the fingerboard? And where can I find a vintage style truss rod?
That rod should simply pull out at the headstock end. If there's not enough to grab with a pair of needle-nose pliers, remove the neck pickup and snake a long piece of 3/16" dowel into the rectangular hole you see in the end of the neck where it's glued to the body. Tap on the dowel and the rod should come out enough at the headstock end to grab with pliers. Pull it out.
Grind both ends of the rod off more or less flat. The longer end should be re-tapped to fit the nut (probably 10-32). The shorter end should be cut to be roughly 3/4" shorter than the threaded end, and then filed or ground at a 10 degree angle like the other rod.
Re-insert and don't forget the tape, which can be redone if it's nasty.