EDIT - I managed to find a few copters on Amazon so if you are interested in getting one of these pre-modded and ready to drop into your machine, send me a PM.
Alternate process for Helicopter mod install (no grinding or sanding)
I got my helicopter in over the weekend and decided to install today. Many thanks to the brave souls before me who originally figured this out and shared with all of us... I wanted to see if I could find a way to install without having to grind away the bottom or deform the top in order for it to fit. Good news is, it can be done quite easily, and without having to take apart the copter. (unless you are trying to also do the cockpit light mod.
Basically with a pair of large needle-nose pliers, I grabbed the original rotor and with a couple of rocks back and forth, you can snap it off leaving a perfect guide hole. I also use the same pliers to snap off the lander gears. The remaining part of the landing gears may fall into the body of copter but they will come out later when you drill the larger holes.
Then on my drill press I used a 5/32" bit to go through the guide hole at top and straight down to create guide hole in bottom. Next, using a stepper bit on drill press I make a 1/2" hole through bottom plastic, this is the size of the shaft in the game you will be sliding copter over.
The trick to this method is to go with a larger hole on the top. Using the same stepper bit, I drill out top hole to a 5/8" hole, this allows for the washers and bearing to sit inside of the copter (instead of above it) and gives us the clearance needed without having to grind off the bottom of the copter.
You can see in the final pictures that the copter sits in perfectly with just enough clearance for the blades to spin and all without grinding away any material. You don't need to do anything to secure the copter, it naturally sits in the perfect spot and doesn't move at all. I also decided to remove the remaining hex posts (since they were only there to hold original helicopter plastic) and just put 6-32 nuts in place to clean that area up. I also did as others have done and placed a small dab of hot glue on the rear propeller to hold it in the perfect position to make sure the main rotor misses it during rotation.
Everything spins and functions as it should and it truly looks like it could have come from the factory this way.
11 (resized).jpg12 (resized).jpg13 (resized).jpg14 (resized).jpg8 (resized).jpg9 (resized).jpg1 (resized).jpg3 (resized).jpg6 (resized).jpg16 (resized).jpg