all my info is just scribbles on paper i worked out when i have put efi motors into various cars.
i do know for fact that speedo sensor pink/blue is +12v, purple is signal to ecm, and black/white is earth. from memory i believe the speedo signal is brown/yellow after coming out of the dash which then goes into ecm pin A10, if you are using the motor in a car without a commodore dash then you can wire the purple wire directly to here and you then just need to change the Pulse Per KM in the tune to match.
also on the under dash plug normally to power a loom on my test stand i put ignition into the pink wire, which can be traced back to ecm pin A6, auto/manual switch is also on the same plug grey wire and goes to B10, and then there is the TCC lockup solenoid, which is the light blue on that plug it goes to pin C7.
all this is from this diagram
http://www.oldholdens.com/temp/carstuff ... gram_b.pdf
also i use some of the wires from the grey engine bay plug, like the one for the fuel pump, A1 ecm pin, this is the +12v to the fuel pump relay on the 86 pin, then there is the check engine light, this is in the aldl plug and also comes out on the under dash plug as brown/white i believe and goes to ecm pin A5.
i use the engine coolant wire too, the one that normally feeds the dash sender, i change it out for my own sender and run it to my in car gauges just keeps everything in the loom nice and neat, and you can also use the blue wire from the oil pressure switch to feed into a dash oil pressure light if you have one or want one.
not that hard to work it all out with the diagram infront of you....
the only info i have of the internals of the gearbox wiring is this:
it shows on the left how it works, and on the right how i modified it to allow a T700 to work behind my 202 without having the delco ecm controlling the torque converter lockup.
how it normally works is if its in 4th gear and gets the signal it will lock the TCC, however if its too hot (OverTemp sensor) it will let the ecm know this and lock the TCC to try and cool things (i believe) so i changed it so aslong as it was in 4th gear and below certain throttle (the vacuum switch) it would lock the TCC, so when i would come into a 60km zone i'd just downshift to 3rd, probably not the best for fuel economy but best i could do! and the vacuum switch worked very well, when overtaking or up big hills and such it would unlock the TCC but still kept the safety in there for the overtemp.