MONTE CARLO Help Eliminating Dash Harness Wires

If you're using one of those GM crate engine setups (ie Connect and Cruise) for your LS swap, those come with the ECU, Harness and a Fuse/Relay panel that has a built in CEL (see pic below). It also has a loose wire you can use to wire up a dash CEL if you wanted one. It would also include it's own OBD-2 style communication link connector.

Do you have the wiring diagram (service manual) for your year/model or are you just flying blind with the wires in the harness? The best way would be to review the factory diagrams for those circuits to be sure anything you plan to remove won't be needed for your LS swap. For example that connector (C437) pictured left of the Lamp Drive Module usually has several wires in it that are part of the CCC ECM Power/VSS/TCC/PN Gear Select etc. which you may still want to use depending on the transmission in your swap.

The Light Driver Module and ALDL are likely fine to remove, but check those others more closely would be my advice.

HTH

Depends on what you intend to use that was factory installed. If you can rewire the dash lights, cig lighter, radio, power antenna, speakers, then yes, you can chuck all of it.

I’ve always left all of the accessory wiring so that all of the steering column functionality is still present. But to each their own.