Been doing a bit of research and it seems 'modern' tanks get field modifications by there crews aswell.

This M1A1 photo'd in Iraq has what appears to be splash armour fitted to the turret roof, a night vision device fitted to the TC's calibre 50, another calibre 50 mount above the main gun, a shield with bullet proof glass fitted to the loaders weapon and at least 3 hand held search lights lying on the turret roof. By the way, this isn't the TUSK version, it's too old.
Cheers
John