Lynn,
Thanks for that but as I said,
mae maxima culpa on that one. When I read your missive, I went back to square one to see why/how I stuffed that one up, and that explanation is above. All became crystal clear when I reefed out the original doc copies from Bovington, in the light of knowing the correct nomenclature. And AWM 126 didn't help, as it just has 'Carrier No.2 Mk1' without further elaboration.
Nice job with your text. A printed copy is going into the reference library, of course.
Mike