My car was originally v6 2.8 and was swapped by a tbi 350 and now i removedall the wires from ecu to engine but these 2 plugs from ecu to under the dash were just unplugged and wish to know exactly what are these?

do they effect the gauges? headlights or what?

please let me know coz 2 days more will try to start after swapping tbi to carb!

thanks