Head replacement 1.5/ 1.6 need advice

In the long running saga of my engine I've found out my 1.5 GL cabrio has a scirocco 1.6 GT FR coded engine with what appears to be 1.5 head on, and certainly a 1.5 inlet, exhaust and Pierburg carb. The head is sounding a bit tappety and blowing blue smoke occasionally so have got hold of a 1.6 rocco head that should be a match for the engine. I've got a weber and 1.6 inlet to fit but not sure about the exhaust manifold? The exhaust is a 1.5 eith the big C clips and is new- can I keep it?

Also, what work should I do to the head before I fit it? Condition is unknown so I'm assuming that just that just doing stem seals is okay?