We have horrible self adhesive vinyl (not cushion - the stuff that's more like Lino) tiles, on top of the original 1930s quarry tiles which we'd like to uncover. We can easily get the tiles off with a heat gun, but is there anything that will remove the sticky stuff that's left without damaging the quarry tiles or the grout in between them? We've been told it's likely the tiles are the damp proof course too so we have to be careful not to destroy that!