On Fri, 16 Jul 2010 04:34:26 -0700 (PDT), Tim
wrote:

The only thing I would worry about with fuel tanks on the swim platform
would be my ability to get on plane at lower speeds.

I have been wondering that myself, but That's left to be tested on the
local lake first. And instead of making tank enclosures, I could use
the same full-tank weight simulation with bricks.

If you do have a problem with that, you might be able to fix it with a
Doel-Fin or similar.