Bridgestone Kabuki - rear brake disc removal
 

I picked up a Bridgestone Kabuki to build into a flatbar road bike for my girlfriend. Not the greatest platform, perhaps, but it's in good shape and very orange; with blue tires, it will allow her to show her support for her beloved Florida Gators - this makes her happy. I am smart enough to recognize the inherent value in this.

Anyway, I'm going to do away with the heavy and nearly useless rear disc brake arrangement and replace it with a standard sidepull caliper. The disc caliper came off easily, but my question concerns the disc itself. It appears to be either pressed or screwed onto the hub. Does anyone happen to know how it is attached, and if screwed on, which way it is threaded? Thanks.