I replaced my shift cable earlier this season and have been hoping I've adjusted it correctly since. I've got the little plastic tool and I think I've adjusted it correctly but I've had some issues. The other day it stuck in Forward. I removed the drive and the cable end came out of the "clamshell" holder. I reconnected the cable end and put the drive back on. Went out for a bit and did not happen again. Also it seems to shift hard. When on the trailer running on the hose it makes a loud clunk and knock going into both forward and reverse. Theres only a faint noise when in the water but it still feels harsh. Every once in a while it will skip going into reverse, almost like it's skipping a gear tooth or something.

The other day I was at my marina talking to a mechanic and asked him about adjustment. He said you HAVE to use the locator shift cable tools like the ones shown below or it won't work.
tool.bmp

That doesnt make sense to me. The cable is a specific length. If I adjust one end with the correct Merc tool it should be the correct length on the other end as well. Am I missing something? Or maybe I have some internal probelms that I'm chasing.