Thank you all for the quick responses.

I did notice the box moving side to side & now that it was mentioned, it moved upward a littel bit too. The box is securely in place and I could not move it just by pushing on it. Tonight, I will put a pry bar against the box to see where the movement is coming from and check back in.

Does the ps box bracket attach to the frame rail or the k-frame?
I am trying to think what that area looks like without the ps box attached. Could someone post a picture of this area without the ps unit bolted up?

Thanks again.