I finally cracked it! The screenshot below is from the second half of the mission, after you have hijacked the truck and are driving towards the compound...

1. Approaching from the north-west corner of the picture, reverse the truck carefully down the steep slope at A.

2. Tell your stupid squadmates to stand BEHIND the truck and HOLD position. You may have to yell it or draw them a diagram in crayon, because they are barely aware of what's happening.

3. Run back up to the main road and hide from the traffic behind the ruined buildings. This gives you a stretch of cliffside from which you have good oversight down into the compound.

4. Use a silenced sniper rifle to headshot each of the 5 guards marked as X on the picture. It's easiest to move east to west. None of the guards vision areas seem to include any other guards if you time it right. All being well, your squad should tell you "all clear", which means you're almost done.

5. Check the mini-map for any enemy vehicles on the road, and when it's clear, run back to the truck and ignore your moronic colleagues. Just don't even look at them, they are a disgrace to their uniforms. Honestly, it's a shame you can't fire them or force them into early retirement, they are a menace.

6. Drive the truck to B (and drive very carefully, it's probably pretty badly damaged and can't take any collisions with anything at all!).

7. Slowly proceed through the automatic gate at C and around the building to the back of the compound at Z, and park up. Once parked, DO NOT move the vehicle again!

8. Exit the truck and if you are paranoid, use the Rebel "Spotting" thing to scope out the compound near to you. If that is clear, then you're good to run, carefree, to the entrance again at C. Grab the nearby 4x4 truck, conveniently placed for your escape.

9. Drive back up to B and then onto the main road to freedom.

10. On the way back home, berate your team-mates for being useless at their jobs. This part is optional, but feels like the right thing to do.

I finally cracked it! The screenshot below is from the second half of the mission, after you have hijacked the truck and are driving towards the compound...

1. Approaching from the north-west corner of the picture, reverse the truck carefully down the steep slope at A.

2. Tell your stupid squadmates to stand BEHIND the truck and HOLD position. You may have to yell it or draw them a diagram in crayon, because they are barely aware of what's happening.

3. Run back up to the main road and hide from the traffic behind the ruined buildings. This gives you a stretch of cliffside from which you have good oversight down into the compound.

4. Use a silenced sniper rifle to headshot each of the 5 guards marked as X on the picture. It's easiest to move east to west. None of the guards' vision areas seem to include any other guards if you time it right. All being well, your squad should tell you "all clear", which means you're almost done.

5. Check the mini-map for any enemy vehicles on the road, and when it's clear, run back to the truck and ignore your moronic colleagues. Just don't even look at them, they are a disgrace to their uniforms. Honestly, it's a shame you can't fire them or force them into early retirement, they are a menace.

6. Drive the truck to B (and drive very carefully, it's probably pretty badly damaged and can't take any collisions with anything at all!).

7. Slowly proceed through the automatic gate at C and around the building to the back of the compound at Z, and park up. Once parked, DO NOT move the vehicle again!

8. Exit the truck and if you are paranoid, use the Rebel "Spotting" thing to scope out the compound near to you. If that is clear, then you're good to run, carefree, to the entrance again at C. Grab the nearby 4x4 truck, conveniently placed for your escape.

9. Drive back up to B and then onto the main road to freedom.

10. On the way back home, berate your team-mates for being useless at their jobs. This part is optional, but feels like the right thing to do.