Mine is a little different from the ones posted...it's quite possible different models/dealers have different installs. My alarm box used a small adapter harness to plug into a factory plug that ran right into part of the under-dash harness...I was originally trying to find some kind of spliced connection to the starter wires but couldn't find one. The alarm box is branded "mitsubishi security system". Anyway, here's what I did:
1) Removed lower dash (2x 10mm nuts behind switch blanks, 2x screws at bottom, 3x screws behind both the fuel door and the hood pull levers).
2) Removed alarm box (attached to crappy bracket behind dash speaker location).
3) The bottom of alarm box has pinouts for all the connectors (picture attached). The only 2-pin connector on the box is the starter lockout control. Pretty thick-gauge wires (blue w/ black stripe and black w/ yellow stripe). I took the harness off the car and the box, cut both of the starter lockout wires, and spliced them together.
4) Plugged the small harness adapter with the spliced wires back into the dash harness and just left the alarm box off the car. Tested the ignition, works great.
Also removed the shock sensor that was just zip-tied to the base of the steering column. It's a small 2x3x0.5 box with a small adjustment knob on the side.
If I was doing it again, it would be really easy to reach up under the dash and just unplug that single connector from the box and jumper it or something, which would leave the alarm in place to keep the keyless entry, door alarms etc working. If you are looking for this box, just reach up under the lower dash on the left side...it's a cheapish-feeling plastic box with four white plastic connectors on one side, and one dangling white wire that serves as an antenna. It's pretty much directly below the left driver's side air vent. That is, if you have the same alarm I do...seems there are a few different installs.
Also, while digging around in the dash, I realized why my red led push-button wasn't working. The installation uses these crappy pin connectors that just come apart with the slightest tug, and the ones for the "button" part of my led button were unplugged.
Anyway, now the car doesn't have a starter lockout anymore so I'm certainly happier with the whole thing. I had the battery go flat once in the middle of nowhere and that's when I realized my key fob didn't work reliably anymore. Put in a fresh battery but had to try the button 40 times or so before just the right squeezing made it send an unlock signal. Seems like it's not a great idea to have a starter lockout (that can't be overridden with a hidden toggle or something) on an overlanding vehicle.
Have a picture of the detactable alarm harness as well but pic won't upload off my phone for some reason...