The problem is that
@copper had a point of reference that allowed him to compare to know something was missing without using instrumentation. We don't know if
@borski's car is a good reference point or not (exceptional/average/poor). It's a single example. After you get REW and a UMIK, you can compare your graph to what
@copper recorded but you would need two people of comparable size seated in the same positions with the mike in the same position and play the same source material. You'll get a reasonable result by yourself.
The ideal environment would be an empty car with the seats set to a replicable position (all the way back or forward) with the mike hung a set distance from the ceiling but that wouldn't have been any fun for copper and borski. Then copper would arrange a meet up for the Bay Area group and test each Air to establish if results across cars is consistent. Then the rest of us can replicate the test and compare. Empty car would also eliminate borski jumping up and down in his seat as the source of the 2nd shelf.