What is the easiest way to apply static simulation to 4 wheel drive vehicle with a frame placed on it, in order to check the stress & displacement data of that frame? (Solidworks)

I need to apply some static simulation analysis, which need s to be done with minimum error. The simulation is to be applied onto a Steel structure made from angle irons & square tubes. The whole structure is supported on 4 wheels (Two rear drive & two front casters). Just like the below posted design structure.