My trailer is a break-frame converted power boat trailer. I bolted two 2” X 2” galvanized cross beams just like any other cat trailer…but instead of putting rollers or cradles on the ends of the cross beams I bolted carpeted 2” X 8” PT planks (running fore and aft) so there is approx. 6 feet of contact with the bottom of each hull. To unload the boat just pull the pin on the trailer the stern goes down/the bow up with very little effort…push the boat off or even drive most of the trailer out from under the boat. It makes it a lot nicer to reload too since you don’t have to lift the bow onto the trailer…just winch it on…and no the sail box never gets we either.

As far as submerging your trailer…while I don’t have to do that with my cat trailer…my power boat trailer goes in till the fenders disappear under water…it is rinsed thoroughly with fresh water after every use. I have had no problems with it what-so-ever.