I have a 1986 Stingray with a 120 Mercruiser. I am having problems shifting. The problem is with the lower shift cable. Before I attempt to change the lower shift cable I wanted to make sure that is the problem. I have removed the lower unit and the stern drive unit. I am to a point where I can see the shift slide at the bell housing. I also removed the cable from the shift plate. I try to move tha cable by hand. If I hit the end with a rubber mallet I can get it to slide in, if I yank on it with vise grips I can get it to slide out, I don't think it should be that difficult to move. What would cause the cable to hang up at this point? Is it time to replace the cable? Thanks for your help.