For jeeps, APCs, rafts, and the C-47 (or any other vehicle where there are passengers not interacting with objects in the vehicle). Sets the animation for a vehicle position, namely how the lower body is animated. These animation states are defined in Animations/AnimationStatesVehicle.con but SeatAnimationLowerBody will accept any animation state of a lower body, so you could use an animation state for the player crouching with a gun, also e.g. Lb_Crouch (These other animation states are defined in the various other con files in the animations directory).
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