Don't ground an exhaust pipe please. They aren't exactly the strongest thing on earth and can easily crack. I found this out the hard way when I first started working line service and needless to say the customer wasn't exactly happy.

I'd suggest a towbar lug. Pipers and many other low wing aircraft often have a grounding tab near the filler neck. Cessnas not so much.

Take it slow when fueling. The pumps don't have a shutoff like the one for your car has. If you can see in the tank make sure to stop with a little space. If you're like me and too short to see in a cessna tank when on the aircraft steps you might have a blue waterfall (gasfall?) streaming over the flap the first time.