GODDAMN HOW
theres a method that people probably don't use.
Slide kick enemy, then circle to their back and do the grapple move. You can disarm enemies when their backs are turned.
so jump out of the truck, disarm the first guy from behind.
grab weapon, shoot other dude.
Then wait for the two other guys to come close, slide kick, get behind, disarm, grab weapon and shoot.
Then just get close enough to the big gunner to shoot him a few times.
then you make your way out!