Yea the suction line is 3/8" which is good. But the return line is the thing to have with today's gasoline and it could be used if you ever go fuel injection.

I use all 3 lines on both of my running cars and they have been driven a lot in extreme conditions. The third return line sure makes the fuel pumps job a lot easier.

My cars are old school with mechanical pumps and I still use the returns.