I've decided to try a home-made manual jack plate. 4" angle aluminum, some stainless fasteners, and some scrap oak plywood glued together to make the motor board. I have the concept down and have everything cut and put together as a mockup. My question is.....on the wood. What do you guys do to seal the wood so that it doesn't soak up water? I will be trying it with my little 25 yamaha on war eagle boat, if that makes any difference.