I am thinking of replacing the aluminum holding tank in my 1992 H 35.5 with a plastic one. I have the catalog from Ronco which Peggy had recommended. I'm looking for an exact replacement[although I would like a larger capacity tank] so I don't run into modifications and changes. I already have an access panel cut into the aft cabin bulkhead so access is pretty easy. I'm sure some other 35.5 owner has done a similar refit.Does anyone have any specs or know which Ronco model or size / dimension works best? Can I go to a larger tank without modifying a bunch of stuff? By the way all the hoses to the head and tank were changed out this past spring, so the job should be easier. Fred Miller S/V M Squared