After falling behind, they levelled thanks to a Conor Bird header and then two goals after the break helped wrap it up as John Dean made it 2-1 before Bird added his second of the game.
A late Sleaford penalty wasn’t enough to spark a fightback from the hosts.
Wellingborough Town are also looking to finish the season on a high and they claimed a 4-2 victory at bottom side Sileby Rangers in their penultimate game of the campaign.
Jack Wisniewski scored twice while Ibrahim Akanbi and Andy Hall were also on target for the Doughboys.
In Division One, Burton Park Wanderers maintained their recent good form with an impressive 3-0 victory over Bourne Town at Latimer Park.
Raunds Town’s faint hopes of gaining promotion were ended as they drew 2-2 at Buckingham Town. The Shopmates twice came from behind to earn a point thanks to goals from Ty Clark and Adam Randall.
Rushden & Higham United suffered a 3-1 home defeat to Huntingdon Town, despite a goal from Ben Fitzjohn while there were also defeats for Irchester United and Thrapston Town as they lost 3-2 and 2-1 to Long Buckby and Oakham United respectively.