Anyone done a strong 400 build ?

Not mine bit I found someone selling a fresh build with dyno video on facebook market place. It made 600 Hp at 6,000 rpm on 91 pump gas. They are wanting 10,000 for it. Is that a good deal or not?

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That is definitely a good deal considering about $ 2800.00 of mine is just the intake and carbs that's not even counting what it would have cost to weld , port the tunnel ram & resurface all machined areas