Just placed the gas tank that came with the boat in place. It's just a hair too high by maybe 1/8". The seat kind of rocks on top of it with no one is sitting on it. With weight on the seat, the tank deforms slightly so that the seat settles firmly in place. Is this the kind of tank you all have? If not, what are you using?
(http://i1062.photobucket.com/albums/t486/sail19/IMGP7838_zps66f5f257.jpg) (http://s1062.photobucket.com/user/sail19/media/IMGP7838_zps66f5f257.jpg.html)
Oddly our tank looks just like that one, but it is made by Moeller, and is a 3.2 gallon
It fits perfect, without issue.
I purchased ours on Amazon.com, This was its full name
"Moeller Scepter Topside Marine Fuel Tank with Gauge (3.2-Gallon)"
Under my past orders it says it is unavailable at this time, but if you search amazon it might come up under a different seller, or might also come up on the internet at Defender or Jamestown Distributors, etc.
Mac
Thanks Mac. I'll look around for it.
I'm using the tank 3.2 gallon pictured here. Works fine for my 2 cycle 5 hp. I actually set it up on some glued down UHMW strips and don't allow the tank to sit on the embossed fiberglass ridges of the cockpit sole. Plenty of room.
skip.
I use a 3gal OMC gas tank. Metal, fits in there perfectly. Image Here: http://img.auctiva.com/imgdata/3/7/1/0/1/0/webimg/576926510_tp.jpg
TG
Looked more closely at what was causing the problem . It was the gas cap that was making contact with the seat. I filed off enough of the top edge of the cap so that the gas tank now fits. Thanks for your input.