Chuck, I can't believe this, but I've got the exact same problem! Roush 351, 1000 miles and just started the same leakage. I closed the hole with JB weld which stopped the leak, but after reading this thread I see the problem. My problem is I'm not sure I can remove my water pump without removing the engine. This is an SPF and the Roush has a large plate for the alternator and A/C that goes over the water pump. I see the rust you got, but I'm still having difficulty understanding how the coolant might get past the rest of the gasket into the timing case? Arggh!