Favorit Meta system immobiliser - idiot's guide to proper removal (help needed)

[anewman]

Favorits had an aftermarket immobiliser by Meta Systems installed. It seems likely that at this point in their life these immobiliser keys will be failing etc.

I have searched the internet, forums and here and found no definitive guide on how to remove it, and thought it may be a good idea to try get together an ultimate idiot's guide with the help of some of you knowledgeable people out there - to make removal as easy and painless as possible (there have been some posts of people chopping the wires and being unable to figure out how to get it back together).

In my car, the immobiliser unit itself is placed on a bracket under the instrument panel although I understand some are placed at the bottom of the pillar in the passenger side. There appears to be 7 black wires placed such that it is difficult to identify where they go to and from.

It seems reasonable to strip a little plastic off each wire (keeping them separated and ensuring they don't short out) and have some labels ready. Grab a multimeter and find a good earth. Use the red to probe all wires, labelling them as their function is determined.

Only wires I can think there will be are...

+12v constant
-12v ground (could be tested for by looking for continuity between wires and a good ground, but probably best to do this with the battery negative disconnected?)
+12v ignition switched (tested with key in the "on" position)
+12v crank input (tested with key turned to crank position with immobiliser on)
+12v crank output (perhaps disconnect the starter motor, and disable the immobiliser with the key and crank the engine seeing which other wire/s of those left turn 12v.)

If I am right, there should only be 5 wires that actually disable the car, or is there one I have missed? Are the other 2 wires dummy wires? Or do these diable, for example, spark and fuel pump?

I assume you simply need to then cut all the wires, join the +12v crank input with the +12v crank output one and properly insulate the others? So only 2 wires need to be joined to disable it? (Or in my case connect them to my alarm's in-built immobiliser circuit).