I recently had to shorten one of my pitch trim springs, and I scratched my head quite a bit trying to figure out how to do this without mangling the whole spring. I finally figured out an easy way to do it, so maybe this will help others trying to do this little task.
First, decide how many coils you want to remove, and jam a small flat screwdriver all the way through at that spot:
Then, run a larger screwdriver through the middle of the spring, and wiggle it past the little screwdriver. This will hold the whole spring nice and straight, but also separate the extra links so you can grab them with a needlenose pliers:
Now just hold the big screwdriver and bend all those links away:
Now, there might be a safer way to do this, but I found I could remove the excess links by just hitting them with the edge of a grinder wheel like this, and then I could grab them with the needlenose and just bend them until they broke off at the weakened spot:
Leave the last link intact and just grind off enough to leave yourself with a hook, or whatever shape it is you need!
Seems pretty straightforward now, but it took me a while to figure out and I didn't see any other tips about it when I searched!