Capps led the points standings heading into the last round, before Gauci drove his Nitro Express '57 Chev to a personal best time on the night's final pass to defeat the L.A. Hooker Funny Car driver.
Fellow Australians Paul Messineo and Nathan Pierano scored enough points throughout the event's three rounds to finish second and third in the event's unique format.
Capps was impressed with the event organisation and support from fans.
"Congratulations to Rick on his win, I'm glad we got to put on a show for the fans," Capps said.
"I'm humbled with the level of enthusiasm for the sport of drag racing in Australia. I had no idea that Australia followed our sport so closely - it's pretty cool."