Are these heads interchagable from the non turbo to the turbo version?

The head itself is the same, the valves and cam are different.

Using the turbo head on the non-turbo without changing the cam will result in low power.
Using the non-turbo head on the turbo without changing the cam and valves will result in in low power and burnt exhaust valves.

holy sh**! I have a 1984 in my garage with a 1981 non turbo head in my garage with a blown head gasket and very worn valve guides.