Brian, you bring up a good subject here. Proper grounding is extremely important for an electrical system to function properly but to often overlooked is the grounding or bonding of the fuel tank to disipate static electricity. Many people accept the installation of the tank through steel hardware and attachments alone will be sufficient, in many cases it may not be especially if the structure has been painted or powder coated. I have a SS tank installed on powder coated frame rails, the gauge circuit is grounded from the sender to the frame rail but I am going to take another look at my tank installation and look at installing a bonding strap. Being in aircraft maintenance, I can tell you that bonding of everything having to do with the fuel tank and fuel delivery system is imperative. Thanks for bringing this up.
....Doug.