The trunk roundel, at least on mine, was fixed on with thin black double-sided tape (and it's GOOD). To work it loose, I used a 1" putty knife (plastic one I never thought I'd use, but came in handy) with a thin cloth behind it to protect the paint. The rear took more work than the front, since you can't work from behind it unless you want to remove the inner trunk panel (For a roundel!?!). I used adhesive remover (Goof-Off) to clean up the tape & residue, then replaced it with new double-sided, cut to size. I didn't expect to need it, but it's crucial for the rear... From the looks of it, not only will the roundel not stay seated very well without it, but water getting in there could work it's way inside the rear panel.... Yuck.
Done this way, roundel sits perfect, no water entry, and it's all good. (Another useless mod complete- LOL)
Hope this helps.

Yep, if you like em, they even come for the wheels...