Is it possible to apply the load where there is no physical part?

Good Day all,

I am trying to see the reaction of the bus structure/frame when applying brakes.

Please see picture below. The tires are fixed and the load supporse to be acting

at the centre of gravity (horizontal axes). But the C.O.G is on free space.

I need any suggestions on where would be the best area to apply the load?

Thanks in advance.

SolidworksSimulation