When playing tank ambush level, get to the part where your marines stay behind and protect the radio tower and stuff. If you dont have a sniper rifle, kill the lady with it and take it or somthin. Then, when you are about to go down the slope to the White Skulls, STOP!! Instead, dont turn and keep going in the opposite direction of the radio base. When you get to the ridge thing, snipe the guys in the FOLLOWING order.
1:Take out all the guys you see at the other NK base.
2:Take out the guy thats standing by the rock just to the right of the NK base.
3: Turn, and find the place where the White Skull Grenadier shoots the last tank, and snipe that guy.
4:Now, shoot the NK guys down on the road below you. NOTE:If you shoot the guys below you they will all start shooting at you.
5:Go down the hill and take out everyone else, then finish the mission.
This helps keep your life up a LOT!