How about a riser gasket, an 88 would need new ones for sure. If it is stock there should not be a problem, I had 88 454s and the riser gasket leaked and took out a cam lobe. Is the oil like milk?

The riser has a valley on top that directs the water directly over the exhaust outlet so I'm adding a two inch extension to the end of that valley so the water will flow that much further past the outlet and hopefully it will not suck the water back in the exhaust.I will also check that my riser is 2" above my out let. Thanks to all for your help