Hi Preston:
There is many, many items which will remove graffiti It's not the Graffiti (Paint) it's the surface that's the problem.
Oven cleaner will remove paint from a smooth polished metal surface, so will WD-40, or even hand cleaner. You will have problems when it's on a porus surface, cement or cinder blocks. Metal building SOME times are OK, but, I ran into one the other day that did't work out so well. Allways test a small place to see if you can remove the paint without harm to the surface.
I belive there is a company that is ownered by a man named Walt he has a good cleaner, You might contact him for some additional help. Think he is in the Cleaner Times links, can't rember his co name Sorry.
Read lables and stay away from any product that containes petrolum based chemicals, they will leave a dark stain.
J Prewitt
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