VY wiring transplant into WB

[shorts]

HI....

Before you all ask why.... I started a project to drop an LS1 into a WB panel van. After rebuilding an engine and transmission (4L60) I was left with a few issues to solve, like no speedo cable output, computer / wiring mods for the ECU and general location of things, like Airconditioning... So now I have a firewall cut from a VY including dash, cluster, BCM, steering column and keys. Currently working on the metalwork.

My question is the comms between all the units. There are a number of things I will need to solve, like immobilisation, ABS and dash responses to different sensors like fuel level. And later engine tuning. But for now how does the BCM ECU comms work and which needs to be programmed or is there a pairing process. I am new to hacking these kind of systems but am preparing to be able to mod these systems, so this is the start of my research and any info appreciated.

Thanx in advance

Craig