One relatively easy way to get this achievement is to have two people playing The Package on Legendary. Have one drive the scorpion, and the other run ahead and kill as many enemies as they can before dying. At this point have them respawn on the Scorpion and simply repeat the process.
Note that the player only needs to drive the Scorpion up to the door of Sword Base, because it will not go any farther.
A possible solution with just one person is to have them beat the level up until the opening of Sword Base, and then simply walking back to the Scorpion and driving it through the now unoccupied level.
The achievement does not require that the Scorpion not be destroyed at all, just that it not be destroyed when they reach the door of Sword Base. Thus if the tank is destroyed and the player is either killed or reverts to a previous checkpoint, they will still be able to get the achievement.