[wolfox]

Before I would blame head gaskets, check your lower intake seal. The plenum is divided into two parts, and if the lower plenum gasket goes - well it starts mixing coolant with oil pretty quick to make the mess you describe.

Edit: Rent or buy ($12) a coolant system pressure checker. Put it in place of the radiator cap and pump it up to operating pressure (15 lbs). If she doesn't hold, and you see fluid leaking somewhere between the heads, or pouring out the back of the engine to drip down your transmission bell housing, it may very well be your lower intake seals.