Wonder anything special for led moving message
re noise, as always, if the 'rules' are followed nothing 'special' is required.
re LED signs
With LED moving message you are in for a ton of surprises:
You need be lightning fast, LEDs, as opposed to CRTs turn off immediately and sensitive eyes can catch flicker at 100Hz.
You need mesaure ambient light and regulate the width of your unblank accordingly or you will end up with something that either disappear in bright light or burn holes on the retina in low light.
If you decide to multiplex, you need a full MPX cycle for every 10msec or less ot flicker is visible.

Have fun, it is

Erik