I had a hunch you had no idea what you talk after going through your posts. PA soldiers improvised a covering from inside on the rear window of second cabin. Coverings were also brought up on sides of the rear open area usually painted as flags and an armoured capsule used for Machine gunner, but that protection is never enough.
STOP spreading mis-information about staff cars.
Brigadier level (one star) and above are authorised staff cars for personal use. Staff car can also be taken out station (outside the city) through an indent made from GHQ. A staff car driver may wear civilian clothing after office hours, because the staff car can be privately used at any time. The officer can drive the car himself and can give authorisation to somebody else (apart from driver) to drive the staff car.
A 4x4, usually Land Cruiser/Defender is also authorised for use apart from staff car.
Another vehicle with civilian number plate is also authorised for use, whether personal or professional at certain posts.
This should give you an idea now why 2 or more vehicles are authorised for one officer.
Apart from this, administration vehicles like pickups (Hilux etc) and high roofs (suzuki Bolan) are also authorised to be used, whether personal or professional. For lower officer ranks, these can be had on payment also.