After the mission starts, go East, i.e. towards Ditadi Abandoned Village. Your destination is the camp in the upper part of the village, but do not take the main path, because the area is heavily guarded and the enemies have the advantage of height. Walk around the village from the North or the South, thanks to which you get a perfect view of the entire camp and you will locate all four Walker Gears without any problems.
Walkers can either be destroyed or fultoned. The latter is a better idea, but you need the CARGO 2 for that, which allows you to extract heavy cargo.
If you want to destroy the walkers, start firing the rocket launcher at them. Do not let the enemy soldiers get on the Walker Gears, because they are well-armed (one of them is even armed with homing missiles).
If you want to steal the machines, enter the camp carefully and neutralize the enemies here. Do not fulton the Walker Gears too early, because this would alarm the enemies and they would man the rest of the machines (in such a situation, you would also have to eliminate the operators of the Walkers).