I believe the only ones that are missing are the L-shaped floor braces and the x brace that bolts to them. The panel fit is decent. I would have liked to see better panel gaps if I were putting it together.
That's what I was wondering (if your panel gaps are good or not). By not having the L shaped braces on did you pan get installed incorrectly. Perhaps a dip in the pan. You may want to measure your frame.