I think there’s a correction there…
The lower fairing is the same, the upper fairing is not interchangable. The RD fairing is actually quite a bit shorter in length than the RC.
So NO! the upper fairings on the C and D will not interchange, but possibly with a RC frame you could get the RC fairing on an RD .. but dimensions
around the clocks would all be wrong so I imagine it would look like a right dogs breakfast 😮