Guys,
Have a look/listen to this one from a 1969 US Army Training film on the M-551 Sheridan Light Tank. The bit with the fire control orders in is from 09:49 minutes in. Its very clear and i could see it being quite easy to get some usable edited sound files from? Not every in-game situation is covered but the basic one's are? Please disregard the "Gunner, missile" sequence!! Lol!
Also this tank seem to be engaging every target from 800 metres!! Pity there isn't a few more different ranges included that we could get sound files for?
Enjoy, hope this helps?