If you want something that is off road "functional" and doesn't look too bad, get some chain, about 3-4 foot for each side, and weld the links together at the ends then bolt them to the floor boards. Then weld the center section for a sturdy "step hoop", but leave the section between the bolted part of the chain and the step loose and flexible. What this does is it lets you have a moving/floating step. If you go over rocks then it will move out of the way yet if you need a sturdy step, it is still there for you.
Imagine a squared off U. Then you can get the picture of what I am saying. Kind of hard to explain, but if you got questions of what I am talking about, let me know & I can draw a picture and post it so that you get a good idea.