Interesting thread.
I have a different approach I'll throw out there for anyone interested. After the EFI swap, I needed to change the fuel supply system. However, the key ingredient in my system is the Dakota Digital (DD) gauges.
I put in new Spectra 20 gallon tanks (dual tanks) for an 87. New Spectra sending units for an 87. AC Delco EPI 381 pumps. With both tanks completely dry, I used the calibrate feature of the DD to set the fuel level on the gauge to the amount of fuel in the tanks. I poured in exactly 5 gallons and set it to the 1/4 tank mark. Added another 5 gallons and set to 1/2 mark. Repeat for 3/4 & full. Then I continued to fill each tank a gallon at a time until it ran out the neck. Both sides were an additional 3 gallons.
I know exactly how much fuel is in each tank at any time. Better yet, the DD allow you to add a low fuel warning light. I set the warning to come on when the tank level reaches 10%. It's a beautiful setup. It also comes in handy for tracking engine hours and lets you set oil change reminders. It's like the best of everything. And we all drank beer and learned things.