Sailing from California to Florida via the Panama Canal
As a one time owner of an Excalibur 26, its a nice boat for coastal sailing, but I don't think it is remotely adequate for this trip. I sold mine over 30 years ago and it was already tired, though a year newer than yours. I doubt yours got stronger. In particular, there was flexing in the fin keel that was suspicious, and the standing rigging and chain plates were dubious. Have you gone over every inch? Is your outboard in the well or on the transom? In the well it slows you down because of the effect of the opening under water. If on the transom, it will lift clear of the water in any kind of swell. Where will you store fuel and supplies? Do you have a spare tiller? could you repair the rudder? Is the core intact?
Unless you plan the whole trip in coastal hops of very short duration, I don't think it is realistic, and I am not sure that trip could be done that way.