How do I get someone in a vehicle to mount a weapon turret?

[Drumheller]

I'm doing the demo alamo mission and I have a lot of vehicles with MGs on them, but I cannot figure out how to get the guys in the vehicles to actually man the MGs. Please help? The manual says nothing.

[The Doctor]

Usually, you unbutton them. Use the Open up command and they'll use weapons mounted on the outside.

[Drumheller]

Open Up worked. Thanks so much