What's the right fuel plumbing for a budget LS swap: swirl pot with submersible pump, dead-head returnless, or a junkyard surge setup?

All three can work. What our sources say:

• In-tank pump + Corvette-style filter/regulator (returnless): Speedway's go-to budget setup. The pump is cooled and quieted by the fuel, and the filter/regulator gives 58 psi with a short return near the tank. Good to about 450 NA hp.
• Surge tank: a low-pressure pump (even a mechanical one) fills a surge tank, and an electric high-pressure pump inside it feeds the EFI. This keeps the original tank and avoids cutting it for an in-tank pump.
• External pump: fine if mounted low, below the tank. It's louder and more exposed.

A proven LS swap fuel system (Speedway's guidance):

• Pump: in-tank is best — the fuel cools and quiets it. An external electric pump must be mounted low, below the tank, because electric pumps push fuel rather than pull it.
• Filtration for EFI: a 100-micron pre-filter before the pump and a 10-micron filter after it.
• Regulator: a Corvette-style filter/regulator (58 psi, short return near the tank) suits mild engines up to about 450 NA hp. Bigger power or boost needs a dedicated regulator.
• Lines: 3/8 in (AN-6) is a good upgrade over stock 5/16 for street and mild race cars; 1/2 in (AN-8) for big power or alcohol. Avoid rubber line, keep lines away from exhaust heat, and use two 45° fittings instead of one 90° where you can — a 90° adds restriction like several extra feet of line.
• Pressure: LS EFI runs about 58 psi, so hose and fittings must be rated for it.