As of now I plan to have all the communications on the pilot side. I installed the header tank on the pilot side also. It is not common. It is recommended to install the tank on the passenger side. The tank outlets are more "natural" when placed on the left side too. If curious, I can explain how I thought. I will have one fuel line from the header tank to the engine, one shutoff valve near the pilot's left knee. About the same place the Zenith's demonstrator plane has. The direct line will penetrate the firewall at the left bottom corner. The return line will enter from the engine compartment at the lower right corner of the firewall. After that I am not sure. I believe it will cross the cabin from right to left behind the pedals and go back to the header tank the same way as the direct line does using the same supporting brackets.

I am putting the tank on the left side as well.  With the flap motor on the right side I thought there would be more room to work on the tank and run the hoses, etc.  I'm still trying to figure out how to run the lines forward.  I originally thought that I would run the fuel through the tunnel, use a selector valve on the center console, and the feed and return lines penetrating the firewall just outboard of the nose wheel steering rods.  Then I would run all the electrical lines/antenna wires along the sides of the cabin to separate the fuel from the electrical.

I saw the tunnel installations. Always feel uneasy about the control cable interference. I will run all the communications - fuel, electric, pitot on the cabin side.