“To be honest, the way we rolled out through practice and stuff, it was a little bit daunting,” Mostert told Speedcafe.com.
“I didn't think I was going to get in the (top) 10, but we made some real good progress today heading into qualifying and, as the track got better, we got better as well.
“I'm super-pumped to be eighth; obviously looking at tenths of seconds to try and move forward, but pretty happy with that.”
Mostert's #25 ZB Commodore was seen with the laptop connected early in the 40-minute Qualifying session, with suggestions that he may have wanted a new engine map or was experiencing a coil pack issue.
Team Principal Bruce Stewart told Speedcafe.com that the issue was “More like an electrical gremlin.
“Really, not a massive challenge,” he added.
“I think the pace was there anyway, so, nothing we're too concerned about.”
Despite finishing 0.0511s shy of the one-lap dash, Fullwood's performance drew significant praise from Stewart.
“When you got a car in the shootout, we're happy with that, and young Brycey was 11th, and for a (season) rookie, extraordinary,” he declared.
“Obviously, the rain and what happened sort of dilutes where we were going to be with that car but we've got to step back and say how good this young man has stepped forward.
“He's got super quick pace and it's great to have Chaz in there because we know how to improve the car.
“We'll work on it overnight and see how we go in the Shootout and see if we can put it (Car #25) very close to the front.”
Mostert's and Fullwood's co-drivers, Warren Luff and Kurt Kostecki respectively, are set to take the wheels of the WAU cars when Practice 6 commences tomorrow at 09:10 local time/AEDT.