197 - 200 Exhaust Compatibility

Evening all,

I'm considering retro fitting a 200 diffuser to my 197 at some stage. And a thought has crossed my mind.

Is the 200 diffuser the only difference a 200 exhaust won't fit on a 197? I've noticed many of the de-cats available fit both the 197 and 200. Or is there alot of other mechanical implications such as position of manifold, mounting points etc.
 
Thanks for that.

Already got that book marked at the ready.

But can a 200 exhaust fit a 197?
If not, why?