Counter-attack on Corazol
When I first played this game it was like hell to me; the best outcome was that i made it to the border with every single man in my squad killed. Now that I've found a good way of appraoching this mission.
First, get rid of the Shilkas, of course. Then, lead your squad to the place labelled on the map as "enemy camp" and kill the enemy guarding the camp, and you'll find some good stuff there: 2 T-72M and 1 BMP-2. Get your squad into the tanks and attack the bridge alongside the Abrams and Cobras; you shouldn't be expecting much resistance. After that, move into Corazol along the main road; now that our amour strength is increased by two MBTs and one APC, the enemy presence wouldn't be much of a threat. The rest is just about making it to the border, which should be dead easy.