Thanks for the feedback.
The numbers on the turret were meant to help out with calling fire directions while the tanks were still onboard their landing craft, during the run in to the beach. It won't surprise anyone that this turned out to be not much of a success. I don't know if this is similar to the dreadnoughts.
The cables came with the kit. Modern Tamiya kits, when they have these supplied, come with a nylon-like piece of string that responds well to liquid poly cement, so they can be glued down as desired.