b&m shifters & 8 3/4 rear ends

Xstream, I melted the cable and replaced it with a 1 foot shorter cable from B&M. It made it stifter to shift. Not bad though. Try some zip ties around something.
Check this idea out.... When routeing a batterys cable from the rear to the front, a kit contains some plastic loops to hold the wire. You could anchor 1 or 2 and zip tie it to that. Just thinking out loud.