I congrats on the Cal20. I just this week bought a 1972 Cal 29. I'm faced with the same situation. I have a Yamaha T9 electric start trim and tilt. The boat has an Atomic 4 that is not running. I believe it to have a stuck valve and previous owner pulled head off and didn't repair or reinstall the head. Now it's a bit rusty. I plan on pulling the motor and installing the yamaha then rebuilding atomic if it can be saved. I don't know the pluses and minuses of inboard vs outboard. My first sailboat as well. I will be sailing in Puget sound and San Juan Islands and they can get some pretty stout currents.
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