ballast resistor

[Jesse van Herk <vanherk@domain.elided>]

  Read a couple of digests ago about someone's ballast resistor in their
scout. This got me thinking: why don't I have one in my 1940 K2?
  Obviously I forgot to put one in when I rewired the thing. Don't laugh,
I'm new at this and it runs without one. Anyway, I need info on what to
put in.
  It's still a 6V system, charges fine, yada yada. Where could I find a
ballast resistor that would work, and where should I put it in the wiring
harness? After the starter obviously, before the coil.
  Or am I totally confused about the whole thing and don't really need
one?
  -Thanks
-JvH