With rivals Penrith losing at Bradford we are now four points clear at the top of North One East at the halfway point of the season.
We could stretch that lead with another home game next week against Malton and Norton - but will have to play a lot better to get another important win.
This victory was earned thanks to tries from Aaron Myers and Liam Checksfield – both getting a brace.
Checksfield's first got West off to the best possible start after just five minutes.
Turnover ball in the Dinnington half allowed us to attack down the right with Tim Blades making a strong run for the line from the 22. Joe Rafferty was in support, and when he was tackled just short of the line the ball was quickly moved to the left where Peter Youll sent the young West centre in at the corner.
Southern was wide with the conversion.
Undaunted the visitors fought their way back to equalise with a try from flanker Oli Rodgers. It came after a catch and drive in the right hand corner.
Player coach Jonny West was also wide with his conversion attempt - although Southern came closer with a penalty shot which rebounded off a post.
Dinnington were continuing to give as good as they got taking the opportunity to take a seven point lead after 25 minutes.
It came from a scrum on the West 22 with powerful No 8 Will Marshall picking up from the base and breaking on the blindside to go in virtually untouched to set up an easy conversion.
Our response was to set up camp in the Dinnington half with Aaron Myers finally getting the try the pressure had promised.
A West attack was stopped just inside the visiting 22 with Ryan Painter moving the ball quickly left to Myers who put in a deft grubber kick. He was first to the ball to pick up and dive over to reduce the arrears to just two points at the break.
We continued to attack after the break with the backs looking dangerous whenever they were given the chance to move the ball. So, it was no surprise when Checksfield popped up to score the try of the game.
Peter Youll and Aaron Myers combined to give the 17 year old the ball just inside his own half. He showed the pace which has given him a North of England Under 18's trial to cruise his way through the cover using winger Will Hilditch as his decoy.
Dinnington full back Justin Wilson did his best to cover the break, but Checksfield had kept an extra gear in reserve to accelerate through the tackle to go in at the corner to give his side a 15-12 lead.
He was back in the action on the opposite wing just two minutes later. His break had taken him clear of the first tacklers, and with Jonny West in his way, he opted for chip kick which the Dinnington coach batted into touch to earn himself a yellow card.
That could have been the opportunity for us to increase the lead. Instead, it was Dinnington who came back with substitute kicker Wilson levelling the score with a penalty from in front of the post.
Worse was to come with the returning Jonny West taking his chance to put his side three points ahead with a penalty from 30 metres.
With 12 minutes left on the clock we were suddenly facing the prospect of another unexpected defeat, and our cause wasn't helped when lthe hardworking Ryan Painter and Dinnington centre Matt Shaw were sent to the sin bin after an altercation on the touchline.
However, it was the visitors who suffered the most with Myers popping up to get the winning try and an important bonus point.
Returning winger Scott Butcher had gone close down the left wing before the ball was moved back right where Myers used his strength to shrug off two tacklers to touchdown and set up the conversion for Southern.
The four point lead still looked vulnerable, but we were able to close the game down with Southern taking a penalty opportunity with five minutes left to give his side the breathing space needed.
West: Luke Mallinson, Scott Butcher, Liam Checksfield, Peter Youll, Will Hilditch, Zac Southern, Ryan Painter, Adam Coates, Andrew Rollins, Tim Blades, John Bunter, Joe Rafferty, Alex Barker, Aaron Myers, Dan Boatman (capt).
Replacements: Ross Wood, Lee Maddison, Greg Edwards.
Tries: Myers (2), Checksfield (2)
Cons: Southern (1)
Pens: Southern (1)
Dinnington: Justin Wilson, Andy Trueman, Matt Shaw, Celeb Nichols, James Marhsall, Jonny West, Neil Francis, Marc Schofield, Mikey Leitch, Jareth MacKay, Tom Sheppard, Neil Dunn, Oli Rodgers, Ryan Donnelly, Will Marshall.
Changes: Andrew Pickering, Stephen Leitch, Josh Pierrepoint.
Tries: Rodgers, Marshall.
Cons: West (1)
Pens: West (1), Wilson (1).
Yellow: West, Shaw.
Referee: Mark Harrington ( Durham Society.)