Adding running lights to Lima GWR Parcel Car

[RCP]

I was thinking of adding some lights to my Lima GWR parcel express railcar. The polarity of the motor changes when it goes into reverse regardless if I hook it up to DCC later, so I thought that would be the obvious place to hook up some lights. I was planning on two sets of led circuits protected by diodes when the polarity changes. I am aware that motors can be quite noisy. Is there a better way or should I be adding some form of protection against spikes?

 

Plan so far looks something like the diagram attached:

 

 

[DCB]

You will need resistors.   If using heritage LEDs the white needs a very different resistor to the red as white needs about 3.5 volts to light and Red about 1.9.  Modern China made LEDs in Christmas lights etc which I use seem to work on about 1.25 volts regardless of colour.    To avoid flickering  on DC I would add a pair of capacitors one for forward and one reverse.   For the passenger railcar I would use one LED per seating bay and feed them through a rectifier again with a capacitor to avoid flickers and spikes.

If planning on going DCC wait until the DCC is live as you will only gave to change it all again.