I am finishing some tongue and groove with water based satin polyurethane. Well I did one coat, then half way through the second coat I realized that i needed another gallon. The gallon was applied before I noticed that I had grabbed the wrong can and it is gloss instead of satin. What do you experts thing would be the easiest way to knock the gloss off so that it will match the rest of my satin finish? I was thinking of say 400 grit sand paper or maybe a 3M pad.