Southwell, named United's player of the year a week earlier, moved on to 24 goals for the season with a predatory treble against Stalybridge Celtic at Bower Fold.
He lavished plenty of praise on his United team-mates, whose six-match unbeaten run has secured fifth place and a second successive shot at promotion.
Southwell looked ahead to the play-off semi-finals against North Ferriby United.
VIDEO: Dayle Southwell interview
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