I was able to easily walk up, place the C4, and get out without anyone around.
Basically, I did the first part of the mission avoiding everyone, after the lookout point, I went wide around to the back side of the village at the other entrance. I picked off the guys at the gate, a jeep will try and come around and while prone I shot driver and gunner.
Then since the fuel trucks are closest to that entrance, they blocked visibility to the other soldiers on the other side of the base and allowed me to blow up the trucks easily.
Ok then things get tricky, enemy randomly will spawn indefinitely and you must get out quick or you will be pinned.
I told my team to supress head of me near the generator, planted the C4, then ran back where I was. I jumped over the barricades and ran alone up to the extraction point while my team stayed and kept the soldiers busy(they eventually die).
Enemies were continuing to spawn as well as a helicopter, but I was well ahead of them on the hillside already.