Sorry about this but I don't know who else to ask.  My '87 GL has developed a small power steering leak.  Drops a spot about the diameter of a tennis ball when it is parked after use.  Bad enough, but how do you get the stain off the concrete driveway?  I have tried two different driveway cleaners and several home brews but nothing seems to work.  Forget the $450 for the power steering,  the driveway just cost me $6000 ! Your help please.