The popular former Pilgrims' boss, who helped guide United to promotion from the UniBond Premier League in 2010, has been appointed as the Iron's new manager.
The sides will meet in the first round of this season's Lincolnshire Senior Cup competition on Wednesday July 17 (kick-off 7.30pm).
The winners will subsequently be able to look forward to a home fixture against Stamford AFC in the quarter-finals.