OK Roland... you are killing me here! You have a partial excuse for the caulk, but damn...
The steering extension was custom built by RD and I one night. You won't find that. As for the transom pass through, as I recall it leaked like a seive. I put that grommet over it from a different part and sealed it up with silicone. Knowing what I know now I would strip the silicone off and use 5200 on it.
With the properly sized steering extension, there wasn't much movement at the transom.
The black rubber part is just a cover for the threads on the "eyeball" socket. Peel it back and re-seal.
If you need help let me know. I need to get you an excuse to come down here and check out the twins...
Wes