Will a b/e-fuel tank fit with a modified a-body pan?
Consider one from an '88ish Jeep Cherokee.
20 gallons, driver's side fill.
In-tank electric fuel pump, 70-90 psi (depending on manufacturer), 50ish gph, 3/8 line with a return fitting.
The sender's ohm readings are similar to stock Mopar, but get this, they are reversed. So your gauge will read backwards- empty when it reads full, full when it reads empty. Easy to turn an "E" into an "F" and vice versa on your gauge if you feel so inclined...
Look it up on Rock Auto, tank dimensions and various pump specs are listed under "more information"; maybe it'll work out for you- it's something I've considered in the past but never acted on.