Oil driping from the tail pipe? Daaaamn! First thought is that the exhaust system is full of oil and untill it all burns out it is gonna smoke. The thing is where or should i say when did the exhaust system fill with oil? With the old head or after the head was replaced? If you dont find any PCV problems and the engine seems to run ok. I would check the oil on the stick and drive this vehicle for 1000 miles then check it again. If it is using oil the level should get low in a 1000 miles.
I have also seen an oil bath air filter cause the same thing because it was over filled.

I didn't do it, no one saw me do it, you can't prove anything! "Bart Simpson"