The third-round match was played in Hikurangi.
Manuel was a handful for the Hikurangi defence with his jinxing runs and good combination with wings, especially Lewabuka.
Handling errors, discipline, missed tackles and wrong decisions killed any hopes of making inroads into Mid Northern territory.
Mid Northern could have scored their second try in the opening 25 minutes but flanker Toby Parr lost the ball in a tackle near the opposition tryline.
The team made amends one minute later when wing Lote Palaiti skinned Hikurangi hooker Campbell Matthews near the corner flag to score.
Lewabuka scored the third try and set up the fourth, before fullback Levi Clark dotted down for his team's fifth before halftime.
Mid Western continued their winning form in the second half and No8 Jas Apoua scored in the opening minute to extend his team's lead.
The hosts' first try came in the fifth minute when big prop Dilot Pefeleti ploughed through multiple tackles.
However, he spent 10 minutes in the bin midway in that half when referee Stephen Ball gave him his marching orders for not rolling away in a ruck near the Hikurangi tryline when Mid Northern were hot on attack.
Hikurangi coach Alastair Rickey said the B team he was forced to field because of injuries to some top players performed well.
"Not the best result but we hope to get up to speed in the next couple of weeks. Hopefully we get three guys back from injury for the away game against Wellsford next week," he said.
Mid Northern coach Craig Edwards said his forwards lifted their game after a disappointing round two loss to Old Boys. His team will host Otamatea at Hukerenui this weekend.
