Finally got around to putting my new tank with the POR15 tank sealer kit onto the bike. Everything came apart real easy and would go back together easy except for one question. On the backside of the tank there is a drain plug. Does this need some type of sealer put on it before I put it back in so it won't leak? If so, what type of sealer? I don't want to get everything back together, gas it up, and then have it leaking. Thanks!