I just recently completed my Fat Bike build. I went with a Charge Cooker Maxi 2.0 Fatty
I also went with Dave's Tangent Ascent with a 3210 Astro flight motor.
I got everything pulled off the bike. (Pedals, Crank, BB, and Front Derailleur)
While waiting for my motor to ship, I went to work on the lighting. I ended up using 2 Ultrafire-UL2 7 Cree LED lights, and a Voltage regulator that can drop pack voltage to 6V to work with the lights. This was the original setup, this regulator is good to about 3A, but I've since found one that can handle 15A that I've swapped in its place.
The other issue I had was the cheap rubber band mounts that hold these lights on. On rough singletrack these heavier lights bounce all over the place. I was able to find some flashlight mounts that I took apart and mated to the lights so I could mount them upside down, and much more securely.
Looks effing cool
The day my drive unit arrived I was pumped. It showed up on my day off and I got right to work. Everything was going smoothly until I went to put the chain rings on. The wide chainstays and 32T gear presented a problem.
This changed my 40 minute install into an all day event. I tried spacing the bottom bracket. Which worked, but then I couldn't get the crank on the other side all the way on. I tried a smaller ring, but a 30T narrow wide is thicker (to stop the chain from hitting the adapter arm. This just made problems worse. In the end I remembered my frams is cromolly, and the chain stays have a cross member, so I took a 5LB sledge and massaged the chainstay in.
This is how it looks mounted to the seat tube.
Here's a good shot of the drive train.
The bike came with a SRAM 10 speed cassette, and X5 shifter and derailleur. I wanted as much range, and low end torque as possible so I used a 42T wolftooth cog. Its running 34T X 11-42 now.
I had to mount the speedo pickup to the front brake line to get it close enough to the magnet to work.
And finally a couple finished shots of the build