Mike Spera wrote:

3M also makes an "eraser" for decal glue that often works on the decal
itself. The unit chucks into a drill and has some sort of rubber wheel.
It was made to remove the glue holding side moldings to cars but we
found it useful for other cleanups like this. Not sure if it is still made.

It and others like it are still made. I didn't post links to the two I found
because they're pretty expensive.

George Patterson
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