Blown headgasket. What's next?

No over heating at all. There is a really bad spot on cylinder 6. I'm guessing rust stains? The truck sat for about a year after the wreck. I started it every couple weeks and drove it around to try and keep it from seizing or whatever else. But as previously mentioned, the coolant system pressure tested out good yesterday. So i wouldn't think it's from coolant. The rest of the cylinder walls have some slight and shallow up and down scratches. You can also see the thick oil buildup in the header from cylinder 4.
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