For the the game on a Monday, I will trial the following......
MMG's - With early tanks having thinner armour than their WWII counterparts they can pin tanks with normal ammunition, if a hit is scored, on a D6 roll of 1 -3 the tank receives a pin.
They can also be supplied with armour piercing ammunition which will give them a +2 penetration modifier, use the standard rules for this.
Grenades - Squads can have dedicated "bombers" they are treated as tough fighters and can re-roll any wounds scored in close combat to score a further wound. They can also throw their grenades at enemy in cover up to 6", the distance in inches as to be equalled or beaten on a D6, if a hit is scored the target receives D2 pins.
Close Combat - Now that pins are not lost when units engage in close combat, if you have less pins than your opponent you can roll an extra D6 for each pin marker you have less than your opponent.