Use those Max Nanosuit pod thingys, then pick up alien weapons like the xpac mortar. They have increased strength and unlimited ammo when you are in max Nanosuit. Search around for other max nano and alien weapons.
LOL, I only discovered the effect of the pods in the final boss, I used to shoot to make them explode and kill nearby enemies
I killed this miniboss using cloak to hide behind obstacles to recover, shoot, cloak, move under cover, shoot again... Remember to enter armor mode before shooting
There is plenty of ammo, JAW rounds and REX charges in the place, so not a problem.