This is the best set up for the grenade boost. 1. get on top of hut. 2. stand at very back of hut against the wall. 3. line up grenade with very edge of the hut. 4. left click throw. 5. The grenade will land far enough away to let us boost on harder setting, make sure to eliminate the 2 enemies that follow the truck so they don't get to the informant.