Dual tank fuel line routing

[liftlawssuck]

Question about fuel line routing on an 82 K10 with dual tanks. Owner had removed pass side tank and solenoid valve when we got it. Put tank back in and new valve in. I have 3 lines on each sending unit. 6 ports on solenoid valve. I know where they all go but want to confirm my thoughts. line size on sending units are 3/8", 5/16", and 1/4". The solenoid has 2 3/8" and 2 5/16" fittings on 1 side and 1 3/8" and 1 5/16" on other side going to fuel pump. 3/8" being the supply and 5/16" being the return. However the fuel lines on truck for the fuel return is 1/4". The 5/16" lines go to the canister for vent. So is that correct that the return fitting on valve is 5/16" but the return line itself is 1/4"? None of the rubber hoses were there when we got it so I can't match up the weathered old hoses for placement. I just don't like the thought of putting a 5/16" hose on a 1/4" line.

Thoughts??

Thanks, Brian