You can e-mail info(at)bottlehead(dot)com and let them know that you need to buy a SEX 2.0 C4S manual, and they'll hook you up. If you don't have the manual for your kit, now might also be a good time to get one.
If that packaging has been sitting around for a long time, the four HLMP-6000 diodes in the bag may need to be thrown away and replaced with new ones. This depends a bit on the humidity of wherever all this has been sitting around, as the HLMP-6000 will slowly absorb moisture over time, then it will tend to all blast out during soldering, which can damage the diode. If you live in a dry area, or if the bag has been sitting in a climate controlled area this whole time, you're OK to use them.
-PB