Terry, I think it might be these pdf's (example). I downloaded all of the available ones if that helps.
02-21 EXHAUST MANIFOLD.pdf
02-21 EXHAUST MANIFOLD.pdf
I have the Triumph Stag Graphic Catalogue. Took me ages to scan it and clean it up as it was NOT A4! It has a listing of all the part numbers in numerical order and where the parts belong. It's quite an old document, so some parts only applicable to later models may not be included. Website address is in my profile.
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