Come in at the Outpost from the West. This will easily let you see all the soldiers after a short while of observation. This outpost has 2 Heavies, 4 Soldiers and a Sniper. There is also a single Alarm Post.
Head up to the Outpost and go to the Southern entrance. Throw a rock against the wall bordering the Outpost. This will lure on the Heavy Soldiers out so you can get a take down on him without drawing too much trouble. Give it a minute and some of the soldiers will notice the dead body. A pair will come to investigate. Take them down in quick succession.
Now head over to the Western side now. There is a small doorway there you can get through easily. Slip over to the left and behind the sheet of cloth. Turn to the right and throw a rock toward the Heavy. Be sure to aim away from the building to avoid drawing more than just him. Lure him over to the cover you are in then take him down. Be careful of the Sniper though as he does have a good vantage point.
Let things sit for a minute. This can lure one of the guards nearby over to the body to get him to investigate. Take him down, once again, when the Sniper is not looking. Now move over to the building nearby now. You have the one soldier left in this building. Get into the room and throw a rock inside it. This will lure the remaining guard inside. Take him down. Now, just pick off the Sniper in the Tower before he spots you.