You don't need tons of men to charge a position. You will need plenty of men to suppress the position. If you have three squads, use two of them to suppress the enemy while the third squad advances on them*.
When the American troops run short of ammo (especially the recon units), order them to move over destroyed Nazi units to pick their weapons. Note: the other teams will not pick up weapons as they have pistols and rifle grenades. Order them to fire within 8 to 9 meters to use up their ammon. Order them to move through the destroyed Nazi troops to pick their weapons. They will pick up all non anti-tank weapons except heavy machineguns, machine guns, etc.
The Americans usually place the 57 mm AT Guns in positions where they can shoot the side of the Nazi tanks when their flanks are exposed. This forces them to keep the AT guns away from the victory location that you are defending as the Nazis.
Start the game in Debug mode, then press KEYPAD ASTERISK. A boot will appear in the place of the mouse pointer. Place the boot over anything on the map and that object (tank or solider) will be destroyed. Press CTRL + F7 to win the game.