How do I disable F/alarm on 99 Jimmy?

This car has a factory alarm which is not functioning properly. It will go off anytime if feels like it. The customer want it remove. Where is this unit located? Or best way to diable it permently? I show him the fuse to horn for the time being until I get some information from you guys. Thanks. Be careful whose advice you buy, but be patient with those who supply it.

|FCTRY ALRM DISARM|lt.green            |- |purple plug at BCM *1       | *1 The BCM is located to the right of the accelerator pedal below the radio. The plugs on the BCM face towards the drivers side. -if you want to permanently disable it ground it. -if you want to disarm when unlock or retmeo start, use a wire that may says "disarm" w/ a relay to properly ground it.Houston,TX

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