Limonene....is what my wife's company uses to make 3M Adhesive Remover.

:rock: :rock:
I'm having Christine get a five gallon container for me...
Oil and tar are complex chemical structures, most organic materials that don't evaporate too quickly will work, Marc's comment about baby oil is an example...organic, won't evaporate, great for removing tar from skin with out damaging skin. Silverback has the best solution, Christine developed the chemistry years ago.
By the way you can buy Limonene from my wife's company (Petroferm) in 5 gallon cans...but you will not like the price, or you can stop by my house and pick up a little and have a Corona while we compare trucks.