I sure wouldn't give away 2 acres. Present him a copy of the new survey, from a lawyer if necessary. Before you put the new fence where it belongs.

Old fences and old surveys were more likely to have errors (when the chain breaks it gets a link shorter) and need to be straightened out over time.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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