A programmable logic array integrated circuit device includes a plurality of regions of programmable logic disposed on the device in a two-dimensional array of intersecting rows and columns. Each language indicator may be ranked according to a priority of the language indicator for determining a most-preferred language for a user. The navigation system is installed with an arbitrary orientation at an arbitrary location in the vehicle turret, and adjusted at this location, without requiring a complicated adjustment mechanism for the observation system, or attachment to the elevating mass.