1.&2. First , I am not sure what the "thwart" is, but it appears that it is
an inboard location. The only inboard tank filler setup that I would or
could live with are where the tank fill fitting is mounted to the top of the
tank and has sufficient diameter so that you can see what is happening in
the tank as it fills.Otherwise you are going to get overflows in the part
of the boat where you ride. Not good.
This type of fill would be about 3" dia. and would be expensive to buy and
would require a 3" fill nozzle on the tank. What I would do and what I
recommend to you is you go ahead and run the hose under the deck and up the
hull sides to the gunnel and mount your fuel fills there, on top of the
gunnel, one for each tank. Ditto for vents. Put the vents on the hull sides
so the overflow or vent outside the hull. Also be sure to have the vent
about 1' below the fills so that they can overflow before your fill does.
You can put the suction cup catch containers under them to catch fuel. It is
helpful, I think , to have the vents under there respective fillers so it is
obvious to anyone which fill they are associated with. As to whether the
inboard location is safe or legal, it may depend on you ask. But I would not
want it in any case.
A quick check of a Boaters World Catalogue has flush fills for about ten
bucks ea., vents about five bucks, 1 1/2" diameter fill hose six bucks a
foot. You could shop around and beat that. But the this stuff ain't that
expensive, go ahead and put it where you will be happy with your boat.
--
Ron White
Boat building web address is
www.concentric.net/~knotreel