I was in the Auto Industry for over 14 years, You don't need a heat gun, a simple blow dryer will do the trick, make sure area is clean, put hair dryer about 6 inches away from Badges, and after about 1 minute sometimes longer, I use a gardening glove or leather glove and slowly loosen the badge up, then use goo b gone and remember to clean and wax immediately otherwise in not to Long you will see a difference in paint appearance and color.
I have to laugh at how many times I have heard about and scene the results of impatient people with Heat Guns completly jack up their paint job,
No Heat Gun Hair Dryer