Hello......working on a 67 firebird. I have this little bub hoder that was tied in to the dash lights (gray) wire. Does anyone know the corret mounting location? Looks like it might have been mounted to the top of the ashtray carriage? Throwing light onto the top of the console? Also wondering where it tapped into the gray wire? Maybe off of the heater control light? I dint see a loose gray wire under the dash.