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

Just run some ptfe hose and call it good. Easy to route, cheaper than stainless hard line, and will last a long time.

Cheaper? Cheaper how?
20 ft of ptfe, no connectors or fittings, no straps for mounting, $100
Summit RacingĀ® PTFE Hose SUM-220985

3/8 stainless steel hard line, pre-bent, factory routed line $85.

1971 DODGE DART Right Stuff Detailing Front to Rear Fuel Lines YGL6903S