The backrest will fall forward if you have it adjusted close to the bars.(forward of the pivot point).
I raised my bike , so I flip it forward , hop on , and flip it up behind be , and I'm ready to go.
Takes all of 3 seconds once you get the hang of it.
I have been looking for a medium small tool pouch to strap to the backrest , that would hold it up nice if she was bothered too much.
It adjusts quick at a stoplight with one thumb, if you wear thicker clothing than you thought.
A thick rubber band would work in a pinch if you needed.
I flip it down and set my helmet on it when I'm parked , makes a good flat spot for the helmet.
It's very well thought out.
Mick

 

Maybe I could Velcro it to the back of her Tourpak?

It too far back and she cannot use the backrest on the Tourpak..

 

A really short bungee would do it.
Mick

 

I just wanted to say thank you for taking the leg work on this. I have been looking at this for a couple months, and didn't know if it would work with my mustang seat. I love the mustang seat just couldn't see giving it up. I will be ordering one, as soon as I can. It is the best option I have seen for the bike. Just one question though, How does it attach to the side of the bike? Is It both bolts in the back? Or just the front near the seat? Can you take some close ups of how you modified the bar to fit with the mustang. Pics are worth a thousand words for me. Thank you in advance

 

This is what's left when you remove the rest.



There is a button on each side on the outside.
The mount actually goes between the fender and the strut.
To remove , press buttons in and pull to rear.
The mounting uses the screw just above the reflector and goes over the directional wiring , then attaches to the last screw of the strut behind the directional.
To say the mounting is robust is an understatement.
I did mine while I was installing the rear fender LED light , I jacked the bike up and removed the upper shock bolts and then went up a couple inches for hand clearance , then it was pretty easy to complete.
Go to the Harley Accesories site , select the backrest , more info , open the install .PDF and you can see the parts and procedure.
Mick