Fatboy detatchables mount a bit differently. They don't have cams but instead slide onto pegs with a latch which simply closes off one of the slides. I actually thought about looking for a safety torx screw like you use. Our Thule ski rack uses the same method.

 

Oh. Gotcha. Well let me know what size screw ya need. We only use a couple of sizes, but we may have it.

 

Thanks, man!