need some advice, running 3/8" fuel line, how to run, what to use

Agree. Even the PTFE stuff isn’t too expensive anymore.

AN Hose - PTFE Lined - Bio-Fuel Fluid Type

The fittings can be a PIA. Just get the right tool.

I think that's the route I'm going to go. Run right from the tank to the mech fuel pump with 6 AN. I'm running a 408 stroker so the HP will be around the 500 ponies if I'm lucky. IF I need to run an electric fuel pump I can add 2 feet at the tank to the pump and just move the line to the regulator off the mech pump and then to the fuel rail. Sound about right?