Regarding the Ignition wiring and Immobiliser, I believe that they're paired aren't they and will only work with the vehicle it came off? I could be totally wrong but believe a guy who swapped his 1KZ for the D4D had the same problem. You might want to look into that and make sure it'll work with the Hilux ignition barrel.
And I believe the Turbos on these are Variable Vane right? Means Upgrading can be difficult due to the electronics... I have heard the chips are the best way as it'll deal with the turbo boost and fueling all together and can get you better power and economy overall.
You could be correct there Beau.. from this setup and from what I've studied this weekend is that the ignition barrel, the ecu and the immobiliser ecu are paired and set uiquely.. the main imobilising wires are all purple and are well spread across the loom thats left over (pretty much whats left with it running in the youtube vid).
From the ecu (lower rhs) there's the obd diagnostic port, then the immobiliser ecu with unique bar code(matched, with purple wires) anti clockwise next condition relay this turns on the engine light, the oil change and cambelt light etc..
The orange box is the relay integrator which has the alarm for lights left on.. and is connected to the condition relay.. just above is where the ignition system runs through it powers the "ignition on" side of the truck (red wire with blue stripe+). The power from the key goes through here, no bar code on that so a standard part.
The small relay below the engine wount run without this. (thats all I know!)
Middle lh/s under bonnet relay and fuse box (mostly fuses for "on" whilst ignition off) handling main power in, wiring for key etc.. Just above to the left is the glow plug relay..
By the reel of soldering wire is the (white) main earth point and the 13 bit diagnostic port.. Just below is the non ecu under bonnet engine wiring connector with temp sender, oil pressure etc and more.. Out of shot is the fly by wire accelerator pedal above the ecu..
Just a breif not too technical description of whats left of the loom I have cut up.
Had a try to get it going today, read afterwards that if you activate the immobiliser you have to get it reset accordingly by some one qualified, or more qualified than myself! Lol So am going to get my mate to remove the immobiliser off the ecu and test the loom... Dont want to have a dash fire from faulty wiring.
I did the crude way of blanking off the egr by crushing and folding the cut off pipe ends

and emptied the smoke filter so should be a good power gain there.
All good!