This cage is intended to replace the inferior mechanism within the Nerf Scooter's blaster unit. It mounts to the back of the fake barrels, and houses two pairs of flywheel motors for better performance than the stock, dual-shafted motors. The motor spacing is at 43mm - enough to meet the limits of most HvZ games and to be safely within superstock velocities. Since the blaster is angled up on the scooter, further performance will only make it less useful. (Modify the scooter itself at your own risk)
Use of this cage will require cutting off the original cage, which is part of the inner blaster assembly. Further instructions to be posted soon. However, if you're one of the few people that's actually trying to do this, you'll probably figure it out anyway.
Space is tight for all four motors; you can just slip the four of them in past each other. You'll need to pre-solder your wiring harness, then attach in-place.
Naturally, if you've gone this far, you have to rewire the entire blaster anyway. Good luck!