This mission is pretty easy and can be completed alone if you can't find anyone to tackle it with. I did so in a few tries as a Grenadier with a suppressed M-468 (with mounted grenade launcher, of course).
At the start of this mission you'll want to head right and take out anyone near the bridge there. I also suggest taking out the marksman if he is in position up high on the other side of the ravine from where you start. Once across the bridge to your right, neutralize all rebels near the informant, but do not walk up next to him to get him to follow you just yet.
Secondary Objective - Eliminate Patrol: At some point clearing out the area around the informant, you will be notified to take out a rebel patrol before they get away with some intel. They will show up as two yellow diamonds and are easily sniped from the area just in front of the informant.
Objective - Destroy APC: After you've cleared the area around the informant and dropped the intel patrol, continue moving to your right, clearing it of enemies. You'll be ordered to destroy an APC. Use you rifle-mounted grenade launcher. Takes three grenades to put it down.
At this point, I found it helpful to climb to the position the rebel marksman was in at the beginning of the mission. Snipe the few rebels you can see from here and take out the VBL with your grenade launcher. The map should be clear of enemies at this point and you can make your way to the laptop.
Objective - Find Laptop and Erase Info: This laptop is at the edge of the map across the bridge from where you extract the informant. Grab the intel and hoof it back to your informant to escort him to the extraction zone.
Objective - Escort the Informant: I suggest doing this after you have cleared the map of enemies and completed all other objectives. If you do, 5 or 6 more enemies will spawn in the area you are ordered to bring him to. Usually one or two of them are up in the little rock formation.
Objective - Secure the Extraction Zone: Be ready with your grenade launcher as another VBL will come from behind you in the tunnel. Blow it up the moment you see it and be ready to fend off the area from a few guys across the bridge and several more that come from the direction of your original starting point in the mission. Successfully eliminate these threats and it's mission complete.