What I had in mind was putting hthe regulator right next to the tank, and if there IS a vapor issue, either use the vapor return filter to bleed a little fuel back to the tank or use a second regulator at the carb set 1 psi below the back regulator and use the vapor return line as a return line for the minimal return fuel. This way it does not handle ALL the bypass fuel, just the 1 psi difference.

I would think a vapor return filter would be adequate...