replacing hu_entry with another hu_entry w most

[mwhell]

Hi All, 

I've currently purchased a another hu_entry headunit so that I go for the extended cluster upgrade in the future due to my hu entry not having the most connection at the back. 

What do I need to in order to make this work?  I've read about e-sys, but basically I just want to transfer it all across, I'm hoping that it's the same year so I do no net to virginize it. 

Could someone please help with a rough guide on what needs doing?

thanks

PS: Didn't go for nbt evo since I've already got an apple car play box onto the aux