I think its a proplem. I'm not sure, but I dont't think those two fluids are interchangeable. If I were you I would flush the system. I just flushed my PS system by jacking up the front tires off the ground, disconnected the PS pump belt, and disconnected the PS return line at the pump. Then turn the pump pulley with a drill and a 7/8 socket and keep adding fluid. I had a friend turn the wheel from side to side while I added fluid and turned the pulley. Figure on using about 2 quarts. Its quick work.
67 RS Convertible, 355ci, 650cfm, 5-speed, 12-bolt, 3.90 gears. 12.7 @ 110 mph