Or skip Mexico by putting your vehicle on a ferry from Galveston to Honduras. Boogie across to CR and begin the adventure there.
that's not a bad idea, Honduras and Guatemala both have some boating - google the Cangrejal in Honduras and the Cahabon in Guatemala - Nicaragua just got their first outfitter last year
remember that "boogie" would involve two border crossings that each require a minimum of 3 hours and can last 3 days
if you hired me to plan this trip for you the first thing I would do is price those ferries (Panama to Ecuador being the required one) and fuel costs for the mileage - remember that any rig that would make it the length of the continent would be considered "luxury" by CA standards and make you a target. They have guns and you don't.
Don't listen to all these buzzkills from the city.
I can't let you get away with that one... although divulging that you just realized the Darien exists pretty much pegs your experience level
A couple of big name kayakers, one of the guys is from Park City, Utah... I think his name is Seth Warren, drove it in a converted fire truck that they ran on biodiesel - I'd try and read up on that expedition if you really get serious at least to see where they stopped to boat
my original suggestion mostly comes from the fact that there's a lot of bad roads between here and there and not a lot of good paddling
surfing would be a different ordeal entirely, probably still not worth it, but better
If you really get serious, pm me and I'll tell you what I know about the borders in C.A.