Yup, I bought a small bottle of Goo Gone. Worked flawlessly with hardly any elbow grease but the small bottle, 2 or 3 oz I think, was only enough to do one side so I need to get another one to finish the job.
Thanks all. I'd recommend this stuff to anyone as well. No harm to the paint whatsoever either.
And here are a few pics of the decal gummy residue before Goo Gone. You can see some old numbers down below as well. All of this is now gone.
I have never seen decals in so many places. The gas cap above all places was astonishing as well as around the door handles but it's almost all gone as of a few minutes ago.