I've installed and used both 1.5 v constant lighting and the older 16 v lighting "systems" in models. My model of the 409 is scheduled to be operated with older NSL models in my roster. These models have 16 v lighting so I decided my 409 will have a 16 v installation.
Prior post "Sunset NSL Silverliner #3 Lighting Thoughts" dated May 12, 2012 will give you some ideas regarding interior car lighting. In making the 16 v lighting stick for the 409 some hints will be given.
If the bulkheads have been re-installed, they have to be removed. There are a few things to be done to the interior prior to the installation of any lighting.
The motorman's compartments can be removed and If desired the controller and air brake stand can be painted black or completely reworked. The motorman's compartment must be removed at one end to thread the wires from the marker lights inside the dash and up into the roof of the vestibule.
Ideas concerning the installation of the marker wires are nearly the same for the installation of headlight wires. The 2 wires for each marker bulb need to be threaded along the end post of the model. The wires are held in place using bathtub caulking.
The 16 v bulbs in each marker are too bright if wired alone, therefore they are to be wired in series. The wires attached to the bulbs are fragile for this and other reasons too involved to mention here always check the bulbs with a 12-16 v power source after the initial installation and after every soldering, wiring, etc. It's easier to replace a bulb when a problem is 1st discovered than later when more work will be required.
After the bulbs are wired in series the connected wires should be affixed to the ceiling of the vestibule with a piece of tape. When the light stick is finally attached to the ceiling, the wires for the markers will be soldered on to it.
The light stick was made from 1/16" x 1/2" basswood. From experience I've discovered bulbs placed 1.25' to 1.3" apart work out best. to assist in making the light stick a diagram is always made. It helps me to visualize the location of the bulbs plus required landmarks. Any pertinent notes are written on the drawing also. A copy of the diagram can be cut-out and placed in the model to check locations, etc.
This is the entire sheet including notes. The numbers may seem strange without an explanation. Trying to do math in inches plus marking measurements which may be in the 64th's of an inch is not easy. Therefore, the measurements were done in millimeters (mm). If you can't do the appropriate metric conversions and/or measurements in metric, it is about time to learn!
The making of a light stick could be the subject of a post by itself - some other time. In preparation of installing the light stick, the wiring for the trolley pole pick-up has to be done. Brass tabs made out of 0.005" sheet brass were made. Here is one of them installed in the end where the markers are located. Never solder a wire directly to a screw head. You may need to remove a screw some time in the future.
After the soldering is done, the area where the trolley pole screws are located are secured with ACC and then covered with a small piece of tape.
Notice the small stud to the left of the trolley pole base screw in the picture above. The one at the other end of the car was "filed" off. To properly position and secure the light stick, a piece of styrene was attached to the interior of the roof. This was done by drilling a hole in the styrene 1st and then secure the styrene to the light stick with a screw.
With the stud (above in photo) still in working condition, the light stick was installed using one of the original screws and this stud. ACC was applied on one side of the new styrene stud where it touches the interior ceiling. Allow the ACC to cure over night.
While one picture is worth a 1000 words, a brief explanation is warranted. The light bulb is the light for the vestibule. Remember the vestibules of cars were lighted so passengers and crew could move about, load and unload safely. The vestibule in the motorman's area was not lighted. The rear vestibule was lighted even though passengers were not allowed to use it on multiple car trains under normal conditions. Other wires show since the model has been wired-up for operation. The wires for both the vestibule light and the markers have been soldered to the top of the light stick.
The 2 screws securing the light stick to the interior look and are different. One is an original screw which held the LED stick. The other screw is a #2 x 1/4" self taping screw.
The light stick and the bulkheads have been installed. What needs to be done next is to paint the light stick and the interior ceiling an aged or off white color. This will hide the wooden light stick with the pieces of copper foil, the brass metal where the lighting stud was "filed" off, and pieces of tape, and the wires.
Next is the seating plus the lavatory section of the interior.