And if you're still with me, here's the gasket, same thing. Copper everywhere, but in the middle it's black. It did appear to still be holding, but there's room for improvement.

To me this looks terrible, but after seeing a few like this I got the "they're all like that" mentality. And I have to admit this never caused me any problems or worry, but the more I mess with these things the more it bugs me.

If I had the resources I think it would be interesting to see what the temperature is right there, then modify with cooling holes and/or hoses, and measure again.

That one spot is usually the first place a head cracks, which I feel is no coincidence.....