Excellent!
So at the moment I have the two variable TIU ports powered by the two variable outputs on the Z4K, and the Fixed #1 port on the TIU connected to the 14v Fixed port on the Z4K in order to supply power to the TIU.
I might look into the BCR option as well... Especially since I don't know when I can get my hands on 2 PS3 diesel upgrade kits.