Also you can try contacting breakers because some cars, like mine, will have a psir of brackets attached ti the inside of to the boot lid where you store the deflector when not in use. I never use mine to store it to be honest as it remains on all the time because I find it reduces glare for following headlights. I also had a piece of perspex cut to fit inside the frame which is where I mount my rear facing camera.
Tony.
ps. I'll add some pictures later.