Swap or rebuild?

Unless you're talking about the .028" ones from MP, I'm pretty sure the factory gaskets were .038-.040"...

In any case, the thinner the gasket, the more important it becomes for the heads and deck surfaces to be square, flat, and free of warpage. I tried to use the .028" gaskets in mine, and they leaked coolant...used a set of standard Fel-Pro blues and no problems...they're about 0.038" compressed.