My return hose from the fuel rail back to the tank is 1/4", even though the fuel rail barb seems to be 5/16" (previous owner). No obvious issues. All other hoses such as fuel pump to the fuel filter, then filter to the fuel rail are 5/16".

I'm in the middle of plumbing in a surge tank. So now, I'll have not just the fuel rail return using this 1/4" hose, but now also the return from the surge tank using the same hose. Fuel rail returns to surge tank - surge tank returns to gas tank via 1/4" hose.

Replacing this 1/4" return hose with a 5/16" will be a pain in the *** requiring removing the fire wall. Willing to do it if this forum says I need to, but hoping this forum says don't worry about it - 1/4" return hose is fine.