The Pilgrims chalked up their fourth win from five in October, with the other encounter drawn, to move level on points with the play-off places.
Southwell, who bagged his 11th goal of the campaign in Saturday's win, was delighted to continue his rich goalscoring form.
He looked ahead to renewing acquaintances with old foes North Ferriby United next Saturday.
VIDEO: Dayle Southwell interview
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