Kube, how did you shorten the springs?
I tried once, cut a coil with a cut off wheel, then tried to "unwind" the excess; but the coils were too tight and the spring wire was unyielding. Gave up and let the excess slide up in the tube. Slid the clip between the coils on the other side.
Saved the original springs from a bad cable and figured I would take the next repop cable to Brake & Equipment and have them cut the ball off one end, switch the springs, and replace the ball. Haven't had the chance to do so, and probably couldn't even find the springs anymore.