I don't believe there is any real access to the waste tank, at least there is not on our '04. There's a couple of access portals to gain access to where the lines all attach to the tank, and where the level sensors are at, but if were to have to remove the tank, I believe you'd have to cut out the bulkhead forward of the aft cabin, or cut the floor.. All would be expensive, and anything beyond that would be a huge ordeal, and probably cost more than the boat was worth.. Personally, I don't ever intend on accessing that tank in that fashion, and everything we've had to do so far, was easily done via the access portals (cleaning debris from level sensors.. yuk!!).. Again, our tank is located in the center of the floor, just immediately forward of the aft cabin.. Now, the fresh water tank, located under the v-berth, looks to be fairly easily accessible, and wouldn't take much to get it out I don't believe. Again, I don't ever intend to have to worry about it..
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2004 Four Winns 328 Vista
1997 Larson Cabrio 290 - sold
1988 Rinker Fiesta Vee 248 - sold