It's probably a lot easier to open the little black box and take a peak at how the cable is soldered at the antenna end. You could probably cut off the excess at the antenna end a lot easier than crimping new connectors. It's a very simple layout. The inner conductor is soldered to one dipole and the shield is soldered to the opposite one. At least the Flarm antenna was done that way and I'd be surprised if the PCAS antenna was any different.

I haven't looked at the GPS antenna other than to remove the two magnets which are hidden under the sticker.