Supercars approved a revised rear aero package for the Mustang ahead of this weekend's Townsville 500 in a bid to help find parity with the Chevrolet Camaro.
The tweaks to the rear wing and boot spoiler were expected to improve the rear stability of the Mustang and address rear tyre life issues that have helped the Camaro prove unbeatable so far this season.
There was scepticism following Friday's practice from Ford teams and drivers over whether the changes would yield any benefit.
Qualifying then hinted at an improvement, with five Fords and five Chevrolets in the top 10 earlier today.
However tyre life issues reared their head again in the race, with the likes of Chaz Mostert and Cam Waters both complaining of rear instability and high rear tyre degradation.
"It was good to get P1 in class," he said. "Even at the end there, [Will Brown and Broc Feeney] just drove away.
Source: Autosport