Ass the Germans on Grand Campaign at Son Bridge, destroy any M5 but do not kill the men intentionally. They will run away. After selecting "Cease Fire", during the next battle in the area the tank men will have powerful grease guns and no tank.
During the setup of troops, you can click aroundon either side of the black area with "Fire" (use the "Troop placement" trick) to get a head start on the enemy. Use this with mortars, tanks, or personnel. The enemy is there, but not seen.
At the game menu, you can change dificulties. Go to "Custom" and click that button. Then, set your troops to "Very Strong", "Always Obey Orders", enemy always seen, units are fearless, and enemy intelligence always available (causes you to see what enemy is thinking, what weapons they have, and how much ammo is remaining). Put the enemy at :Very Weak", therefore making your troops almost invincible super troopers.