Tom, I use WD-40 and buy it by the gallon. At the marina, with salt water everywhere, we used CRC Marine grade with much success. The boss, a good wrencher in his own right, swore by it. And, it did seem to leave a good protective film. We soaked the engine rooms down with it for winter storage.
Steve
ps
Good chance I'll be living in NH this summer. Keep me in mind for a visit/ride.