With 240lbs on the outermost edge and only 1 nut holding the fiberglass on, the step doesn't budge at all. It feels like it's attached to the frame.
The factory bracket without anything attached weighs ~5lbs; mine weighs ~13 lbs.
Note the extra body line at the bottom of the door indicating this is a revised door with a side impact beam.
See also:
http://www.thedieselstop.com/faq/9497faq/tsb/tsb/95-08-06.php3 
