I just thought of something about my motor!

I have an ABA short block with my 1.8 CIS head. It is still at the mechanics, and I had these questions pop into my head. What I am going to do with the coolant system? What needs to be changed?? Do I have to get the ABA fittings? Can I use the original radiator from the GTI?? Please tell me what I need to do before I kill myself. Thanks, as always!