I put the nozzle in the filler as far as it will go. I fill on the medium setting of the 3 notches. When it shuts off automatically I manually fill until the next automatic shutoff, so one overfill. Then I shut it off and go on my way. I believe the extra 1/3-1/2 gallon will be absorbed by air gaps and other normal things and will not damage my car. I would not go beyond one extra cutoff though.
zeusstx 
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