Two vehicles:
- One damaged vehicle (Tank, AFV, Truck) stopped either at the side of the road or in a field. Damage can be mechanical or combat; if mechanical, it may not be obvious to the PCs.
- A second vehicle, probably a truck outfitted for repair and/or tow parked nearby, large enough to hold 6-10 men.
6-10 men (1-2 providing security, the rest intent on examining/repairing the first vehicle, 1-2 (full crew if tank or recce vehicle) are the damaged vehicle's crew). Security team has assault rifles in hand; the rest are unarmed with small arms nearby (in the repair vehicle).
This can be smaller, with just the vehicle crew and an immobile vehicle.
Alternatively, this can be a damaged heavy weapon (120mm mortar, cannon or howitzer) with and ordnance repair crew.