Applemouse

Hello people of this forums, I acame across this project of Darkside Developments where they have made a track monster of a Skoda CitiGo and my question to you is if and how a CitiGo can be converted to AWD? I read that it had the Haldex rear axle but what just goes into converting it into AWD? How hard is it, what parts does one need, etc. I'm thinking about doing a similair built. Thanks in advance.