The following step can be challenging and time consuming. Be sure to go slowly and have patience to prevent damaging your iPod.
Use an Exacto knife to separate the glue holding the USB port on the iPod. Run the knife along the seam between the two sections of the iPod until the glue is separated. Expect to run the knife along this edge 20-30 times before the glue will be entirely freed.
Continue to run the knife around all four edges of the USB port until the glue is released. You may be able to gently wiggle the knife from side to side to help release the glue.