Thanks for the input. Looking at my own pictures, it does look like I could have bent the retaining tabs a bit more. It was tough working under the car on the ground. When I tightened the retaining ring, I got a nice stop then gave a few more taps to make sure it was seated well. I didn't remove the fuel sending unit and replace the gasket but I did order a new gasket (COAF-9276-A) in case my quick fix doesn't work. I ordered the gasket from a Ford dealer. I hope it fits. If I end up installing a new gasket, I'll go with the Vaseline treatment. I heard that works well.