hmmm redlining the engine wont necessarily to the engine itself any harm becuase manufacturers usually overbuild their engines for that purpose. The reason behind a redline is not to save the engine, but to save the engine components, like the oil pump and any of the accessories like the power steering, brakes, etc.
I know for a fact that the Taurus SHO 3.0 V6 was built to safely rev out to 9500 rpm or so, the only reason it was held down to 7000 rpms is because of the engine components and accessories.