LED strips for walthers passenger cars

I have discovered a less expensive way of lighting the interiors of HO passenger cars. Instead of the costly Walthers units, LED strips cut to size, (available on Amazon), much less than Micromarks, Bridge rectifiers from Ngineering, and 1K resistors. If you have decent soldering skills, a very nice effect can be created inside the cars, especially of they have tinted windows with seats and people. The rectifiers provide lighting forward and reverse. Capacitors have been suggested, but I have not used them, as I am not sure how to... but there are no problems so far. Usually 12 or 15 leds per car

Would appreciate any other observations.
EPS

I went through an LED lighting upgrade for a set of MTH O-Gauge Superliners and eventually converted nine of them for use on my sort-of model of the Auto Train.

My modules consisted of a rectifier (since 3-rail 'O' is the land of AC track power) with a capacitor sitting across the rectifier outputs, and a current-regulator (I believe it's an LM317T ) to provide constant current to the strips. The capacitor smooths out the power coming out of the rectifier and keeps the lights from flickering on dirty track or any other source of momentary power interruptions.

---PCJ

Bridge rectifiers are also necessary in DC operation so that the proper polarity is always delivered to the LED's, regardless of the direction of travel of the car. For anti-flicker, I use 470uf 25 volt electrolytic capacitors which seem to do the job and are still small enough to be easily hidden above the car windows.