Jim, what cars are they running this year? I know you posted a picture of a Mustang on another Thread

T.C. .......Mustang is new for this year. Stretched bodywork to fit spec tube frame like nascar but there are some remnant O.E. parts used such as a-pillars and winshield frame, instrument panel (dash to y'all) , roof and rear window opening, dogleg pillars. An increasing % of parts are carbon/ kevlar.
Nissan run Altima cos originally the series ran sedan body shapes only. Holden run an Opel designed Commodore new last year. Opel designed cos no more GM cars built here. The image posted on "Wheels Up" is the Commodore.
Ford had to go Mustang cos no more Falcon local production here. Camry is the only locally built car.
There has been some criticism of Supercars not having the foresight to modify the spec chassis/cage to accommodate current body styles. Marco Andretti has bought into the Holden factory team now run by Ryan Walkinshaw (Le Mans sportscars 20 years ago) and they say they will "NOT BASTARDIZE" the Camaro body to fit that chassis and suffer justified criticism like Mustang has.
Walkinshaw runs a factory authorized and warrantied conversion business importing Camaro, Chev Silverado and Dodge RAM .........right hand drive conversions, Australian Design Rule compliance (side intrusion, seat belts, tyres, airbags) . They strip ALL these vehicles from front bumper to rear window, weld proper pressed and laser cut patch panels, mostly to firewall, paint, insulate and re-assemble. ... impressive! !!
Note: I'm ex-GM body design so got a bit carried away. ..sorry....still a passion at 66 y.o.

Suggest u go to youtube and search "Supercars slo mo".