An update. I pulled the trigger on a 20" Tohatsu 6hp with Sail-Pro prop and alternator kit to add to the sailboat. I expect to receive it tomorrow.
I was not able to verify whether or not the twin-cylinder four-stroke 8+hp motors would properly fit in the well area without mods. It is a light motor that will be much easier to remove from the well after each trip.
I also was not able to confirm that a 25" leg would clear the rudder, so I went with a 20". I e-mailed a few owers and ex-owners who confirmed that the 20" motor worked good in the well so I went in that direction.
6 hp is a little anemic, but I know it will fit and if I really like and decide to keep this boat long term I will upgrade again after some time.
If the weather agrees I am planning on moving the Excalibur from San Diego to Dana Point the last weekend of the month. I plan to document the move and will post a narrative and pictures from the trip.