Went over to a buddy's one day, and he was changing gas tanks on his daughter's Escort. He had both tanks on the driveway, trying to get the sending unit out of the old rusty-leaky tank. I immediately picked up a screwdriver and small hammer to help.
We both hit that ring on opposite sides at the same time, each at our own cadence. When our 'beats' finally hit together, that ring came flying off. We were both amazed. The new ring went on easily.