Mercury uses a brass, threaded outer shell (both cables) at the engine end with a brass barrel that can be positioned along the threaded area for the purpose of setting the length of the control cable movement at the control box to the required movements at the engine. The center connector has a plastic stem with a 5/16" hole to fit over the threaded stud (both cables) on the engine, locked in place with a self locking nut that a ⅜" wrench fits.....as I recall...don't remember if it's ¼" and 7/16 wrench but somewhere in that range.
As the cables enter the engine, about 1-2" inside the cowling is a double barreled cylindrical receiver where the brass barrels are (pressed into and) secured after the proper length has been established, with a latch that slides over the barrels to lock them in place.
If you don't have such then I suppose you need to get cables adapted to your new engine.
