Mercury with disc brake- fitting mudguards?

[PH]

I have a Mercury frame on the way and am using a BB7 disc brake on the back and want to fit standard SKS guards but not always a rack.
Most of the photos in the Thorn literature show the guards fitted to the rack, the ones that don't are frustratingly from the non disc side! 
So does anyone have guards fitted without a rack?  How/where have you attached them? If it's the the eyelet, how have you manipulated them around the brake?
All advice appreciated, photos would be a bonus

[DAntrim]

I purchased a Mercury with BB7's and mudguards fitted from SJS. They clamp the rear stay above the rear disc and then bend it to the rear clamp - I'll take a picture of the stay when I get home.

[DAntrim]

As you can see 2 metal clamps holding the stay together and then bending out to the fender above where the BB7 would sit

[PH]

Thanks DAntrim, that's very helpful.