Brief history on the car first. 01 v6 auto, converted to ls1 with stand alone wiring harness utilizing a 98 ecm. Has a set of aftermarket gauges mounted to a sheet metal plate in place of the stock gauges using dedicated signals from the ECM or sending units from the gauges themselves.

Im wanting to redo the gauge cluster and include some of the dash warning lights if possible. My hang up is Im unclear on what carries the signals for them and can they be isolated? The original wiring is still there only thing removed was engine harness for the 3.8.

Id like to isolate items like door ajar, trunk open, parking break, more car related items less motor related. Is there a wiring diagram for whats at the back of the cluster and does it include some of this stuff or is it more canbus data interpreted by the OE cluster?

Thanks