Bob - in the 60s, I built around 30 Voodoos, powered by either Fox or Johnson Combat Specials.
We used both bladder and 3 1/2 ounce metal pressure tanks, the latter fed by crankcase pressure, directly out the backplate.
LOTS OF NITRO!!!
We normally mounted the metal tanks butting up to the rear face of the leading edge and then reinforced the area with fiberglass.
We used a single outlet coming out the bottom and a single inlet into the top forward inboard corner of the tank. We fueled from the inlet and then connected it to the pressure line. Very simple, very effective.
Bob Z.