hello all, i have a few questions about the decking on my dory skiff. The inside of the boat is painted white so i want to break it up a bit with some natural wood grain decking. I purchased some fir 1x4s from a mill and want to preserve the look as they are now. Do i coat them with polyurethane now, then make my cuts or wait until all cuts are made and then poly them all at once? There are 13 boards with a 3/16s inch  gap between boards. Also should i sand the primed surfaces before applying paint to the bottom and sides (inside) of the boat. I have already applied 2 coats of primer and am sanded out! Dang near killed me. Thanks for any input