LS Engine Immobilizer install

[huzilulu]

Hi Everyone

The build is going well - I am just about to dive into the world of electrical gremlins! I had a question about the LS Engine Harness / power supply / immobilizer addition:

I have purchased an immobilizer that had an input/output for fuel pump, ECU, and engine start button... basically, until the unit is not disarmed, it does not allow the engine to start, or send power to fuel pump/ecu... also, in the event of a car jacking, it cuts off power to the ecu/fuel pump and prevents re-starts until the unit is disarmed again

Now - I understand the wiring for the start button... just cut the wire between start button and start relay, and wire 'through' the immobilizer...
I am assuming it will be the same for the fuel pump - have the immobilizer in serial between the power supply and the fuel pump +ve lead - but which wire is that on the LS engine loom (on the fuse/relay side, as the actual lead in the engine bay is too far for immobilizer and it would be easier to take the feed from the relay/fuse junction)??

Thanks