Constarr

How do I know if a avic z1 has the z3 upgrade? I just bought a avic z1 and don't know if it's already upgraded or not. If not already done I was thinking about buying the z3 80g hdd. If I buy it I'm not sure how to swap the hdd out if anyone can help me with that aswell. I've looked all over YouTube to see if someone made a video of how to replace the hdd but had no luck.