Hi benny, it's not the spacing that is the problem that I had. If you look at the first pics the caliper does not sit correctly on the stock 1200 strut, the brake pad surface is not in full contact with the rotor.
Also with the drum brake struts you have to weld on mounts don't you? With the disc strut you use the original caliper mounts.
I have some drum hubs that I had on disc struts but was not happy with the lack of location for the bore of the rotor and these do need to be spaced 5mm or so from memory if using the drum hub as you mentioned.