Originally Posted by vswingfield
It doesn't really attach to anything. I tucks into the 90 degree corner formed by the back and top of the compartment that holds the steps. When they are the correct length, you slip them onto the back of the bottom step while raising it a little. When the step is lowered to the correct position, it moves inward pushing the top into the (upper) corner. Easy!
I have one larger one of those braces, and it goes in the center of the step, rather than 2 small ones on the outside. I'm sure the 2 smaller ones are more stable. But anyway, I think this is just to support the lower step; I don't think it'll do much to support a wobbly top step.
Replacement outriggers are surprisingly inexpensive...but the job of replacing them is quite involved, what with all that has to be dis-assembled in order to get at them.