Your question did not state on what type of 1972 vehicle the subject throttle cable is attached. Throttle cables are used on lawnmowers, motorcycles, automobiles, boats, aircraft, etc. Similar cables...
I bought the service manual for my bike. It explained in detail everything I needed to do. If your going to buy the manual buy it online it's usually cheaper.
The engine will rev high and not easily drop back to idle
The gas pedal will not operate smoothly
I'd say this isn't a very common problem, but the cable is easily accessed at the throttle body...