1980-90 Custom Cruiser Gauge Package

I know I need to change the driver's side dash fascia to add it to a car that didn't come with it but my question is: Do the idiot lights still work with the Temp/Voltage/Oil gauge package for the full size 80s Oldsmobiles? Is there a second wire to operate the lights if you install the gauge package sending units? As far as I can tell the dash carrier already has the holes in it to support them. It'd be nice to have gauges and not aftermarket ones. I don't remember the RPO code.

Thanks,
Steve