I use the Paterson 3 reel tank (three 135's, that is) and develop two 4x5 sheets at a time, manual inversion, just as if it were roll film. Emulsion side to the center. They do not float together and thus do not get scratched. Invert gently, of course. It takes 825ml of solution to cover the fiim.
Be sure to keep the center post in the tank - it is part of the light trap.
I've tried to "taco" method, and find that the two "flat" sheets work best for me.