[mamacko]

Hey all.  First time posting to the board, so hope I am in the correct place and don't make any gross errors.

We just bought a new to us 2000, 3100 open.  Bad smell when we use the head and I'm guessing the previous owners never changed the vent filter.  I understand that it should be on top of the holding tank on the port side, but how do we get access to it?  Do we have to lift the entire front cockpit area to access where the engines are?  We have opened the 2 smaller access hatches near the vent location (on the port side of the boat), and also looked under the port passenger seat, but aren't able to see it?  

Any photos of where they found their filter would be sooo helpful!  I don't want to be "That guy" who stinks up the marina with an old filter! 

Thanks in advance for any help!