I have done the same, no screws but glued with Araldit after I have demounted the fender and kept it indoor for 2 days with pressure on the attack point. It has ben working for about 15.000 km til now with no signs for problems.
Have you ever thought af a Corbin - I am a bit bony too, but like the quality of my leather Corbin.
You can get it in UK by:
Corbin XJ900S Diversion 95- Gunfighter & Lady Saddle Seat - Suitable for Harley Davidson XL 1200 (Sportster Custom) Honda CB 750 (Dohc Faired) CB 750 (F Dohc) VFR 750...
I have tried both the MRA spoiler on the original screen and the Puig racing dobble bubble - and my experience is that Puig gives the most smooth wind stream over the helmet. There is a lot of turbolence behind the MRA.
I can highly recommend the German product 'Kettenmax' - it is easy and clean to use:
http://www.kettenmax.at/shop/index.php?cat=c1_KETTENMAX-PREMIUM.html&XTCsid=3d6adc4a8e3c5b7677984ec7d79afcc1
Christian - Denmark
It fits very well, but you have to buy a Top Sadlery tank bag. The cover is to heavy for tha magnets. Or do like I have done, remove the orginal mounting clasp, and mounted another four clasps for my HELD tankbag/backpack, which works very well for me.