OK I'm going to try and do my GOPRO vid this weekend. Any suggestions on postion? Next to muffler, top of car, by spoiler...?

I would really like to do this without it falling off at 120mph ... Want to put it so we can get a better since if we just think it sound good..because inside the car it sounds amazing! So it would be nice to know what we're doing to the rest of the population...are we annoying them with a "tin can" or getting them to say "damn it I should have gotten that Crossfire".. I think it is the second option.