Reason why I asked is that vinyl usually gets brittle, and the glue hard, with age.
I use only a standard hair dryer and a
dull razor blade scraper. New blades tend to gouge easily.
I own a heat gun, but it is WAY too heavy and hot to work with the scraping hand.
I usually get the surface warm, start the decal with the scraper and peel the rest by hand, keeping the heat in front of my working area. Get it too warm, or get the vinyl that is close to the sheetmetal too warm, and it will break as you're pulling it.
Reflective material is THE worst... it's a PITA all around. Standard vinyl isn't too bad.
It sometimes takes a little getting used to.
Sometimes, if it's too old and brittle (old houseboat jobs I've done that sit outside forever come to mind), it will need scraped all the way. Most times this method leaves behind the adhesive, requiring a soaking with mineral spirits and re-scraped, often more than once. Work in small areas. The glue, if not removed, will funk up your sandpaper.
Every job I've done has been "different" in one way or another.
The eraser wheels mentioned above work great too.
http://www.goodspeedmotoring.com/automotive-adhesives-foam-trim-decal-removers/foam-tape-and-decal-remover/astro-eraser-wheel-400e.html
Available in a kit:
http://www.ebay.com/itm/Astro-Pneumatic-232-ONYX-Pinstripe-Removal-Kit-1-Tool-12-Eraser-Wheels-/330870140868
I've seen wider ones than this, with the flappy fingers:
http://www.amazon.com/Dynabrade-92255-4-Inch-Diameter-RED-TRED/dp/B0011WT4PI/ref=sr_1_7?ie=UTF8&qid=1369770452&sr=8-7&keywords=eraser+wheel
3M makes a version, too, but I don't like it. Wheel looks similar, but is comprised of a stack of thin floppy discs on the arbor that fly apart when over-revved.
One drawback to any of the wheels is that they fling balls of material and hot wheel boogers everywhere.
I've stripped a bunch of striped vehicles, but don't own an eraser (have tried them, but don't have a burning need). Same deal with stripper chemicals... never had luck with 'em, have no need.
Have some vintage cans of the sprayable 3M "Woodgrain and Stripe" remover (ha - woodgrain - LOL); use it for stripping gasket chunks from old Holleys...