Re: steering
Teleflex Morse mark their cables within a foot of one end with a series of numbers. I agree that a new system might be your best/safest bet considering the age of your boat. They offer the whole system. Get the no feedback type either in rack and pinion or radial. I have used both. I know rack comes in NFB, not sure of radial....I know mine didn't have it but that was many years ago.
On installing, ensure that you have nice sweeping curves to your cable and as I recall they tell you what the minimum bend radius is. If you exceed it you will kink the inner wire and that is what turns your engine. You DO NOT want to kink the inner cable.
Short story. I bought this 2 year old boat and the steering was unbelievably stiff. In short, the mfgr. came out with the cable from below via a port adjacent to the engine which was too close to the engine and caused a kink in the inner cable. I got tired of fighting it (took 2 hands to steer) and bought a new Teleflex NFB system with the rack and pinion. In attaching to the engine, I redirected the routing to the engine so that I had at least the recommended sweeps in the bends and steering is perfect.
HTH,
Mark