Looks like the general consensus among your facebook 'peers' is that Chaz owned you.
Insofar as being x amount of spots up, that cannot be definitively measured until the end of the season.
Unless you compare where each driver was placed in August 2018 to where they are placed now.
Nevertheless, there are lots of reasons for those driver's improvements this season other than the Mustang alone; including 888 not having their act together, and Lee escaping from the hapless Team 18.