I did it on a day that was about 65 and did not used any other heat. I have removed vinyl and badges from other cars with a heat gun or hair dryer. You just use enough heat to make the vinyl or glue malleable. It does not take much. The idea is not to melt the glue or sticker. In fact too much heat makes a sticky mess. The right balance is soft enough to peel or pull off, but not so hot you can't touch it. There should not be enough heat to damage the paint if you follow this suggestion.
Good luck.

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2007 Tundra 5.7, Double Cab, SR5, Blue Streak

TRD (stickers removed), de-badged, Volant Intake, Zoomers exhaust , Doug Thorley headers, Leer 100R, Bedrug, Curt front mounted hitch, Sirius interface kit, Tekonsha Prodigy brake controller, OEM alarm activation, Wet Okole seat covers, Stubby Antenna, Folding Rear Seat Mod for Double Cab, Unichip,
Carriage Works Billet Grille