Adam Lavin added a third from the penalty spot after being brought down inside the area by a Lawds defender.
An injury to the influential Marc Parry appeared to affect South’s midfield rhythm and Lawds pulled a goal back following a rare error by goalkeeper Conor Rabbett.
With South beginning to wobble, Lawds were given the perfect opportunity to reduce the deficit further from the penalty spot, but Rabbett atoned for his earlier mistake with a stunning stop.
Rabbett’s save seemed to breathe new life into South and Lavin fired home his second of the game with 15 minutes remaining to kill the game off.
South should have added a few more before full time with Kaye’s effort smashing against the post and Nathan Ezair going close on two occasions.