Decal removal

If they are not too bad, a heat gun and plastic scraper will work. Too much heat and they get too soft, stretch, and break. Too little heat and they are too brittle and break. With practice and the right amount of heat you can lift an edge with the scraper and then slowly peel them off in large pieces.

If the are really dry, cracked, and peeled I found the above method did not work as well. On those I used a 3M Eraser wheel.

In both cases I used 3M Adhesive remover to get the left over adhesive off.

Pretty much what BB Tex said.
I use a regular old hair dryer on high setting, peal with finger nails and or plastic scrapper and then clean up with some "Goo Gone."

Moved from Forum Technical Support

I was able to remove a badly cracking decal last year with the methods indicated but there is a nasty ghost left behind. Any way to remove that!?

Use a plastic scraper, not a razor blade----been there, done that. When you use Goo Gone, use the automotive stuff, and let it soak in for a few minutes---the residue comes right off.
The hard thing is to figure what to replace the stickers with.

A single edge razor won't scratch a thing if you use it right.
I'd use a razor blade on the hood of a new car if I had to. Actually do sometimes if there's a stuck glob of sap or something
For me the method is different depending on the how the decal is coming up.
If it's newer and still pliable, usually can get it started with a razor.......or plastic scraper and then heat and peel. The right temp and rate and angle will take the glue with it and make the clean up easy.
Next is scrape/peel with a razor blade, use heat gun if it helps. No heat if they're too brittle. Glue clean up remaining I use lacquer thinner, acetone, prep sol, adhesive remover, etc. whatever I have laying around. Might scrape off solvent softened glue if it's not rubbing off easily.
The most stubborn decals or glue get an eraser wheel on a drill.

ghost are forever,, unless you repaint.

on mine, White body, slight yellow ghost and the ghost are very shinny ...

I use Goo-Gone for the remaining adhesives
and a hair drier, heat gun. go slow. I was removing 11 year old decals.

I used a hair dryer and a plastic scraper also. Not a fun job. I also used Goo-gone to get off the residue.

I see several vendors for replacement decals on the internet. Anyone have a favorite vendor for this?

Set in the sun, heat gun, razor blade, plastic scraper and goo gone. Just be careful.