Theft module

I have a 1996 chevy monte carlo z34, the starter was wired up wrong and it dissabled the theft module,which sends a signal to the pcm to turn on the fuelpump etc,it is not in the wiring diagraham and is not labeled,because gm went to the government and got a waiver to not label the device. Sayin theft went down dramatically.it costs $341 then 300 in labor,where is it located and what does it look like I can’t find any info on it, can u help?