Re: 1959 35 'rude
My friend, there comes a point when its time to stop fooling around and do something the right way. You now have two of the same control box and two sets of unusable cables.
For about fifty bucks, you can obtain a new and properly sized set of cables for your boat. With those cables and a little maintainance on your original box, you will have a control system that works properly and is safe.
I've tried to help you by describing the various systems in use, how to identify what you have, and how to properly replace your worn and/or nonfunctional parts. Whether or not you accept the wisdom of making sure that a control system that must work properly every single time, does work every time (especially in regard to closing the throttle on your engine), is up to you.
I wish you well.