I am looking for information for adding a second fuel tank, I have a 300td that I can take the tank from, I did some googling but I could not find pictures of what I want. I want input on how to connect the tanks, where to put the second tank, I have thought of an electric transfer pump to fill the original tank when it is low and fill the spare from the trunk, but I have also thought of a big supply line at the bottom of the tanks to allow the tanks to balance, which brings me to the need for a stand up tank rather than the flat tank in a td, any advice would help, and would I have to ground both tanks? but don't rain on my parade

 

sounds good, but then I would have to put a second fuel line in, I thought of a transfer tube to level both tanks, if they are side by side