What I eluded to was as shown below - i was going to try and make two of these to pass through the deck of HMS Victory to operate the sails but the weight of all the bits and bobs would have made it top heavy (also I found an easier more hidden way).
As I first proposed, a cylinder inside of which is the pull rod connected eventually to one piece of the crane, the cylinder it sits in is attached to the other crane part, the rod has a bulge along its diameter - like you find on a ball point pen ink tube (it's where the idea came from), the spring is sat in the bottom of the cylinder and the cord or fishing line exits through the bottom say through a micro bore tube fitted to the end of the cylinder and the cord etc is attached to the end of the pull rod, as the cord is pulled out of the cylinder the pull rod is pulled into the cylinder, compressing the spring which cannot get past the bulge in the rod when the spring is completely compressed that's the end of travel, when the cord is released the spring returns the rod to the initial position, thereby there is no need to push the cable into the cylinder and it bunch up, the issue would be the pulling action on the cord transferring through the tubing to the servo, would it give - and just like on the real things some of the tubing could be small bore brass pipe to stop this happening, with hidden bends like shown below to the servo, after seeing the Type 42 parts made in 3D, could the bits be made in a printer with just the thread being added afterwards , just a thought