Paul Dumbrell gave chase early, before falling off the road at Turn 7 on lap nine while under pressure from Fiore, who had earlier overtaken Brodie Kostecki.
Dumbrell dropped to 14th and remained there for the duration, while Rullo sailed on to a 2.6s victory.
Brodie Kostecki finished the race third, followed by his team-mate Kurt Kostecki, Mason Barbera and rookie Thomas Randle – the latter pair scoring personal bests.
Chris Pither (Holden), Shae Davies (Ford), Macauley Jones (Holden) and Jake Kostecki (Holden) rounded out the top 10.
Garry Jacobson struggled in the MW Motorsport Altima, finishing the race 12th while his team-mates occupied the top two places.
Nathan Morcom (19th) bumped Matthew Chahda (20th) off-track on the opening lap, Morcom receiving a five second time penalty.
The second 28-lap race will take place tomorrow at 10:30am, followed by Race 3 of the weekend at 12:55pm Sunday.
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