Well, this is the strategy I recommend.

Enemy group	Frontier	Recommended Unit	Solar Empire	Recommended unit
2 Acid Vets + Several Grunts	Use caution, watch for and attack Recon reinforcement	Bazooka	Kill Acid Vets, watch out for Recon reinforcement	Assault
Radar Array Fort	Attack Light Tank at the west entrance, destroy MG Tower from the west entrance, then break through the east entrance to destroy Radar Array	Bazooka	Break through the west entrance, free the POWs, and attack the Gunship reinforcement	Assault
Fuel Refinery Fort (Part 1)	Support attack against any Acid Vets, watch out for a Recon reinforcement	Bazooka	Bait out the Gunships, then wipe out the Acid Vets	AA, then Assault
Fuel Refinery Fort (Part 2)	Free the Light Tank POWs, then hold against the Recon reinforcements from the north	Bazooka, then Light Tank	Support; wipe out any leftover infantry	Assault, then Light Tank
Munitions Dump Fort (Part 1)	North route--wipe out any more Recon reinforcements, leave infantry near the FR Fort entrance, kill all the infantry along the way as well as the Recon reinforcement, and then summon all infantry to the area	Light Tank	South route--take out the Bazooka Vets along the way, and the Light Tank if necessary, and then get to the entrance of the MD Fort	Light Tank
Munitions Dump Fort (Part 2)	Trigger the counterattack, then move in and break through	Light Tank	Wait for the counterattack to get triggered, then move in and break through	Light Tank
Helipad (Part 1)	Let SE go ahead	Light Tank	Destroy the Gunships	AA
Helipad (Part 2)	Wipe out all remaining defenses	Light Tank	Wipe out all remaining defenses	Light Tank

The idea for taking care of the Munitions Dump is to flank the enemies inside, and make sure that the tanks (preferably 2 of them) have to attack the Frontier, who will, obviously, have their Bazooka vets ready to thin their numbers. If the Solar Empire has to fight off 2 or all 3 of the tanks (hopefully not), the Frontier can quickly get in, then back-attack the west front tanks. All 3 tanks against the Frontier means that the SE can go in and erase all of the infantry buggers as well as back attack the tanks--but Frontier will also have to be careful so that its tank doesn't die.