Moto Nerd

Two seat brackets replace the grab handle, and have a slot where the plastic bodywork fits and the luggage holders are re-mounted using the same allen-head screws.  Then the backrest is affixed with four more 6mm hex screws.

rear-view left
closeup left bracket
outline thing
Backrest w/shelf

And a hammer might be used in an effort to line-up the holes since it’s steel and very robust (resistant to change).
20oz. Eastwing