So the pickup unit is not so cheesy now.
I used a nice piece of round aluminum
Carved a little notch so it had a nice fit.
Drilled some pilot holes.
Drilled out the center and put in a 3/8 fitting.
I even extended the pickup line so that it reached all the way to the bottom.
Made sure my ground wire was attached properly.
Put a little Seal All around the lip, and tightened it down with some more of those nice self tapping stainless screws.
I now have a nice corrosion free plastic tank, and a working gas gauge.
Some days I amaze me.
All the other days are me F-in things up 5 and 6 times to get the end result.