hi there
i agree with jason, you need to contaqt tensid, they can send out sample for you to try, in a very basic format they produce cleaners that act in a similar manner to t cut, in the way that they need to be applied then removed to have a chemical effect on the surface.
i would be more than happy to talke a look at this for you depending on where this is, as you are going to need access equipment, and this will ba labour intensive, depending on the finish that the client requires.
regards
martin sales