Thinking about some plastic strapping material they wrap boxes with - pulled tight over the roof without any glue so it comes off easy - mount the leading edges of the airtabs to it with tape and strap it to the gutters or around the rear hatch opening or even fasten it to the rear wheel wells with hooks and put some VGs on the side too!
n0rt0npr0 - how big a box did you get of them AirTabs - want to send some my way??
I only purchased what I needed which was 11 of them. And damnit, I can't say whether they've made any difference or not because I've been trying to source a 93 GM 6 cylinder computer for $20 since I got them. Ain't found one just yet. My computer keeps on resetting its fuel table optimum - verified by a Tech1 scanner. Yeah. My tank to tank FE has been eerily close for quite some time now.
"You have to know the truth, and seek the truth, and the truth will set you free."
I had a '77 Gremlin (remember them?) with a small scoop-type wing mounted up-side down over the rear hatch window. This served to keep the dust and raindrops blasted off the rear glass. It worked extremely well! Isn't this the same sort of thing the vortex generators (supposedly) do?
Better MPG? The thought never occurred to me...such a tiny gain! MPG gains come from HP reduction...while maintaining a given velocity! People don't seem to appreciate this simple truth...it takes power to move a mass at some velocity. Burning gas makes the power. Less gas (more MPG) to move at the same speed is what a higher FE is about! Stirring the air a bit takes no power...and doesn't make any, either! Small wiggles on a MPG read-out are likely caused by the "noise" of the real world.