Thank you. I knew there is a sequence but never really followed it. But this arcing being with the fuel tank itself I really should be very careful!! Thinking about it now... I MUST follow your sequence from now on.
Fuel and fire are too close to each other here.
Just a hint: When installing the battery cable screws, always attach the positive one first, and the negative (ground) screw last. That way, if your wrench hits a metal (ground plane) part, it won't arc. When removng the screws, remove the ground cable first, same reason.