The reason I did this was because I also made a custom usb chaging port on the left side of my car steering wheel (which is where my phone mount is) and I did not want it to be overly long. In the end it became about 10cm long and works great.
Step 1: Things you'll need and time
Things you'll need:
1. USB Cable $21
2. 30W Soldering iron or better $20
3. Helping Hands (Aligator clips mounted on stand, Radio Shack $20)
5. Wire cutter/stripper $5-10
6. Shrink tubing $6
7. Fine Solder (I used 0.6mm for this project) $7
8. Electrical Tape $1
9. Lighter or heat gun. $1 - $50
10. A Pin (this is not needed for second attempt)
Step 2: Cut and Strip wire
Strip off the exterior white sheath.