My guess is these are the optional wheels for the performance pack.
I base that on this description in the order guide:
19" X 9" (F) 19" X 9.5" (R) Machined with Tarnished Dark Aluminum (644) Available on GT Performance Package (67J)
Are these percentages just for the early production/allocation?
It looks like true “custom” orders are not being taken till April 17th with the build and price Phase 2. It would suck to loose out on my build if my local dealer will not take my order till 4/17.