Correct fuel line set for 1971 Challenger 440 6 pack

[rmance]

What size are the fuel lines needed for 71 440 6 pack? Is there a return line needed? What size?

 

[Challenger RTA]

My understanding is that the factory fuel supply line from the gas tank on 6 bbl and Hemi cars is already the larger 3/8ths vs 5/16ths line. I would go anything less.