Megan,
Thank you for entering the lists in my support, but I'm surprised this topic has popped up again. Following
Slow Flyer's conclusive evidence, I accepted (my #28) that what the Museum had got the real EZ999, which was a Mk.IA. Our search was at an end.
...So the Great EZ999 Mystery is solved at last; I can pipe down now and rest on my oars. My thanks to all who have helped me on this three-year old quest. EZ999 lives still in Narellan - long may it remain so, as a standing reproach to an Air Force which commissioned it, bought it, used it in a desperate time and then turned its back on it...
It was just unfortunate that, having got it, for whatever reason the Museum then had to fit it out with a 0.50 cal Browning (the hallmark of a Mk.IV), complete with a matching rear canopy section, and a "bitsa" instrument panel that was certainly not that of a Mk.IA (or I suspect, of a Mk.IV. either).
There's really no more to be said on the subject. I wish the various groups which are trying to resurrect a second one well, but reckon they're on a hiding to nothing.
Danny42C.