Must build a WELL that the pump, return line filter sock all set down inside and this whole mess sets down in the tank.
Absolutely foolproof. Find Plastic coffee can thing to mount it all in. You can go around 90* corners until you're down to the last qt of gas, works good.

 

Do you have any pics or anything to describe the design of the coffee can mod? Because in my head I am thinking up flaws... but don't really know what you have in mind.

In my mind I see a can on the bottom of the tank, that at some point will empty itself and leave all the other fuel outside of the can?

 

No, its constantly being refilled by the return line. EVERYTHING sits in the "well"...not just the pump. Everything except the float arm.Fluid seeks its own equal level. Because the lateral G forces try to sling the fuel side to side, dill 1/8" hole or 2 in the rear of the "well". This well fills itself by way of the return line and the small hole in the rear allows for self leveling (although not needed really). It will use the last drop of fuel in the car.

If I can find my old sender/assy I will take a pick so you get the idea. I use a more square plastic bottle, and cut a slot thru the bottom edge just enough for the strainer to fit thru and into the tank so its not folded up and blocking the pump suction.
I also use stainless wire or tie-straps to secure the bottle to the metal return tube (cut tiny holes or slots in the plastic bottle for wire to pass thru) so that it stays clear of the float arm at all times & levels.

The benefits are obvious...My pump is submerged no matter what the car is doing or what the fuel level is. I can go hard at corners with 1/4 tank and have no starvation. When I am low on fuel the return line keeps the pump covered and the excess flows out into the tank. This still gives an accurate fuel level since the 1/2 of a qt bottle does not displace any fuel. It simply divides the tank and prevents fuel from escaping the pump when lateral forces would normally sling it against the sides.

Make the bottle as tall as possible to give the best level of protection against windage. The taller it is the longer the hard corner can be when the tank is low. 6" or a little more/less is fine for most. Once you start the project and see it in your hands you will easily figure out the rest,.

I get to use ALL the fuel in the tank since the "well" rest on the bottom and the cross-over hole is in the rear where the deepest part of the tank is, the fuel gets picked up and forced into service instead of flowing to the side.

Also, retrieve the useless little plastic windage tray that used to be glued to the bottom. Its the GM version of what my system does, just smaller and broken away from the suction area.

I think it was a Mobile-1 bottle that I cut up to make the last one because of its shape and the fact that it was a plastic that I know to be petroleum resistant. I have used round bottles, box, but the square bottom qt oil bottle seems easiest to mount and most effective.