You might take special interest for these videos:
eSim introducing their product at the ITEC 2010
http://www.youtube.com/user/eSimGame.../1/EY7D9j9B0lc
Spanish with English subtitles: explanation on how to operate the secondary gunnery sights in the Leo-2E (no lasers, no thermals, no stabilisation, no auto-lead). These GSS's crosshairs may have different designs and functions in different tanks.
http://www.youtube.com/user/eSimGame.../1/bTzObYPz4yo
How the installation looks like in use with the Norwegian military:
http://www.youtube.com/user/eSimGame.../0/OOYqTauIr9s