Re: What is the best option
If it's a single cam ZC head then it will work with the B7 block BUT it's basically the same head. If the B7 engine is complete I'd recommend installing it as is and if you feel so inclined you can use the ZC camshaft in the B7 head. This way you don't introduce potential problems by removing the head. Worth noting is the timing will be off as the ZC camshaft is meant for a taller block, please see the FAQ for further info.