Just got done doing the road test.
Speed was 65 mph
Data points w & w/o were done in 2 direction on the same stretch of hwy. Attempted to take readings in approximately the same spot to keep it controlled. 2 positions on meter, next to my right ear and approximately 4" off the center of the rear deck. Car was 6th gear, cruise control.
With---Without
74.9---76.8---Head
78.6---80.9---Head
76.8---77.9---Deck
79.0---83.0---Deck
I'll take it.