Tank size

[limax2]

The way i read it is that the mesh isnt the problem. Its the solid 14mm of pipe at the bottom where fuel cant get through - you would need to make the entire 40mm pipe out of mesh instead.

You are right, but I think what Deefer was meaning was to do away with the plastic pipe completely.
The 14mm is probably there to prevent drawing any of the crap previously mentioned and also any water that would sink to the bottom.
A way to increase the capacity a little, which has been mentioned before on the site, is to drill a breather hole part way up the tube that sticks into the tank below the filler neck. This allows more fuel in the tank by reducing the air space above the fuel when full. Of course you try not to get drilling swarf into the tank when doing this mod.
I find 200 miles is enough range to keep me happy so I haven't done any of these things  .