During pre-race inspection in the NASCAR Cup Series garage, aero duct parts and/or aero duct opening on the No. 42 car did not conform to the NASCAR rule specifications per the following rules:
20.4.2.d – For NA18D Events, the approved CAD files are the files included below in addition to the approved OEM CAD files. Body components must also conform to the nominal size, drawing number, and part number as outlined in: Table 20.4.2.d NA18D Events. Aero Ducts.
20.4.4.a – For NA18D Events, aero duct openings must conform to the CAD files: Chevrolet Aero Duct Hole Pattern.
As a result the crew chief has been ejected, the No. 42 will start from the rear of the Open, and the team has been fined $25,000.
— NASCAR —-
In addition #33-Austin Cindric failed inspection twice and #13-Starr made unapproved adjustments. They will both start from the rear of the Open as well.