I guess that it depends upon the type of glue.
Need to take care that any solvant used does not react or blister the dash plastic.
If when set it does not pick off then I would try something like lighter fuel - first in an area that is well hidden from view- check there's no reaction with the plastic.
The other product (from builder merchants) is BIG WIPES good for cleaning mastic type products, but again first try in hidden area
Maurice
April 2011