We had the Spirit 175 - the predecessor to your 180. We put a port-potta in the center console. And the rule was whomever used it had to empty it at the end of the day. It was rarely used. Eventually we just pulled it out on the forward deck for use and everyone else just understood to stay focused in the aft end. That and a very bumpy ride home from Bimini (with another boat) moved us to a 208 pretty quickly!
Sorry, I didn't give any good ideas!