Never top off with gas?

[Secret Squirrel]

I have an aftermarket rear tank in my 1969 c10.

I was at the gas station filling up. I set the pump on the slowest setting to allow the gas fumes to cycle out of my tank.

I became distracted by a nice corvette (happens way too often with fast/classic cars). I then heard a dripping sound as I continued to gaze at the vette. The smell of gas pulled me out of the trance but my shoe was soaked. Guess I did not have a good seal.

Since that day my fuel gauge has been way off. I think I knocked the float out of adjustment. It reads half full when empty and off scale when full.

Is that why you shouldn't top off your gas tank, besides the dangers of gas spilling as you drive down the road?

Anyone ever have a messed up gas gauge after topping off?