As I started playing with block detection, I realized that some type of device would need to be on the end of every train. Knowing the location on only the front end of the train provides limited and not very useful information. I found that FVM made some wheelsets with resistors, however finding them in stock anywhere was impossible. I happened across a youtube video that explained how to make my own, so I ventured down that path and ordered the pieces I needed. I picked up some FVM metal wheels, electrical paint, and some 10k resistor chips.
The chip resistor comes in a roll of 200 and the electrical paint should be more than enough for that many wheels. I applied a small amount of glue to hold the resistor to the axle then used the paint to make an electrical path from each wheel. It took me about 30 seconds to do a wheel. I used JMRI to verify the wheel worked when placed on the rail. Much to my surprise, not only did the first one work flawlessly, it was really fast and simple to make.
My plan going forward is to make a single resistor wheel for a dozen or so cars. I see no reason to replace any more than just one per car, and no reason to do more than that many cars as only one per train is really needed. I am starting with the obvious cabooses.