Mooney has been having a running battle with 82V Dennis Black at the past two meetings.
There's a $500 cash prize up for grabs for the best stirrer overall in the series, and watching the way Black has managed to slow Mooney's progress is likely to encourage others to have a crack tonight.
Mooney also has a handy lead over Johnston in the season-long points chase, but the pilot of the 2NZ car will have to call on all his driving skills to stay out of trouble.
Scott Duncan has made no race of the Superstock points this season.
Returning to the track after a serious illness, Duncan has been the model of consistency throughout the season.
John Caird and Jason Pointon have had a season-long battle in the Production Saloons.
Caird has a seven point lead over his rival heading into the final meeting, but in feature race points, Pointon has the advantage.
There have been some great battles in the Ministocks all season long.
In the Youth division, Dylan Smith has a narrow six point lead over Trazarn Ryland-Annabell.
However, in the feature race points, the two youngsters are tied on 27 points apiece and the feature tonight will be a winner-take-all affair.
In the adult division, two Palmerston North competitors have been dominant.
Ayrton Smith has a slender five-point lead over Brandon Jurgeleit.
Smith also has a three-point lead in the Feature Race points over his close rival.
Lastly, there's little in it in the Sidecars.
Aaron Rose and Amelia Stanley have a narrow lead over Mitch Byers and Tony Hislop in overall points, while the two combinations are tied in feature race points, so again there will be a real edge to their racing tonight.
Racing starts tonight at 6pm, and there's bound to be plenty of action in all classes as drivers try to make the most of the last night of full-on racing.
Then everyone will be back at the speedway at 1pm on Sunday for the last day of the season.
There will be opportunities for crew and sponsors to have a drive, before the season finishes with one of Oceanview Speedway's infamous Demolition Derbies. It's a fitting way to end what has been a really good season for the Wanganui Stockcar and Speedway Club.