AWK08 has a wonderful brake setup, and I am glad that hehas plenty of work but sad he is working so hard he does not have time for his passion. Hopefully they will balance.
I don't wish to distract from the excellent design AWK has worked out, but there are other options.
I respectively disagree about the floating Cali/rotor you can use a floating rotor and floating caliper together. In fact it makes it easier to fabricobble. You don't have to be very accurate. I used both together on mine.
Didn't mean to put this in the middle but won't move it. SORRY
This is the same setup I used, Banshee/Warrior/Raptor caliper and master cylinder:
There is no cable park brake on this setup but no reason it could not be used.
This setup is for floating rotor.
The drilled rotor was done on my drill press and seems to work well.
Banshee/Warrior/Raptor master cylinder on a once cable braked Blaster.
Wire cable-guard and cable eye removed as well as back half of mount.
Almost a pound of steel removed, still weighs over 2 lbs.
Lever straightened to gain length and leverage to more easily lock back wheels.
There are 2 types of rotors on Blaster, fixed and floating.
You need a fixed caliper on a floating rotor, and a floating caliper on a fixed rotor.
In the above picts you can see the floating caliper has been fixed with the home fabricated mounting plate.
This is a Ninja 250 caliper setup that would work for a fixed rotor
The problem with this is that you do need the complete package, axle (for the fixed disk mount) and the bearing carrier for its caliper mount. To convert a cable Blaster the setup I picture at top only needs the master cylinder, line and caliper.
Your best bet is to buy the parts you are needing new or used, such as on Ebay. The line is often best bought new. My systems above are all built using used parts bought quite cheap, less than $50.
Steve