Upgrading I3 pro B to dual extrusion

[kstargg]

On another forum post i found a list of parts i would need to upgrade the pro b to have dual extrusion.

I have purchased the following parts:
20a Power supply
mk8 dual extruder
dual extruder mount
Stepper driver A4988

now i am looking for help on what exactly i need to do next, such as flashing the firmware, where do i install the new chip, etc.