Computer Anti Theft

I have a 90 'Olds. Toronado V6. It works great in the driveway. But the second I put it in gear, within 3 minutes, and light anti-theft locks happens.

I have a spare, but I can not find where the computer is in order to replace it. I asked a repair shop of good quality (they guy knows everything about them supposedly) and I found a computer behind the glove box where I was told to look, and it is wrong. I pulled the whole car dashboard, and can not find the right one. I can not even understand how to work around because I can not find it!

HELP!

Try under the rear seat, try chest behind the side panels or try the console. Still no luck then lift the carpet on the passenger floorboard. I have many pieces Toronado trofeo but cannot remember exactly where I got from ECM. Not having the car more. Good luck.