OK, you seem to have moved the goal posts once again. I've completely lost track of your argument.

Sport post 1.

A uniflow tank will help between full and 1/4 empty.

Sport post 2.

Pressure at the pick up is always the same until the level of the spray bar so there is 'obviousely' some advantage.

Sport post 3.

Pressure at the pick up is always changing and there is a difference in 'head between fuel level'? Not a big factor unless off by an inch or more.

So the same as a normal tank then?

A normal tank mounted 1/2 inch low or high will have a difference in head pressure of 1 inch from upright to inverted. Not true because when inverted the vent is under the fuel, the tank becomes a uniflow tank. So will a uniflow tank, which is why I said right at the start (incorrectly) that uniflow would make no difference to the tank height problem.

I think you are now agreeing with me?

I'll say it again for clarity. A uniflow tank will have constant pressure at the clunk/spray bar from full to empty. The pressure at the spray bar will change if the tank is raised or lowered relative to the spray bar

Dave H