Thanks for the suggestion. :)
Thanks, you're right, I assumed that the clarinet in D is a better choice because of the key, not knowing it is a rare instrument. I also didn't delve into the background knowledge of these instruments, choosing them purely for convenience off the list Sibelius gave me. I'm not sure about C score, do you mean the brackets that Sibelius automatically creates for ensembles or the notation in sounding pitch?