There is a discussion somewhere about replacing the incandescent controller bulbs with LEDs in Realtrax controllers but it's a fairly straightforward idea - here's one way:
Not sure if you already have the bi-color LEDs but in addition to the size (3mm, 5mm, etc.) you will see they come in common-anode or common-cathode. Same components, just reverse the diode as shown depending on which type you have.
The turnout terminal diagram is from the Realtrax instructions; if your track power is also from the Z-1000, you don't need to run the black wire from the Z-1000 Aux screw-terminal to the turnout ACG terminal since that common/ACG connection is already made via track power.
I suggest a 1000 ohm (aka 1K) resistor which ought to be bright enough. LED "efficiency" or brightness varies all over the map depending on which specific LED you get but 1K is a good starting point. The resistor and diode are pennies each.
If not obvious, this circuit does not affect what's used for the rotating lens lamp in the switch-machine itself; you can leave the incandescent bulbs installed there even if the controller switch uses LEDs. I'm not sure if there are LED replacements for the wire-terminal bulbs; I've actually made DIY LED replacements for the MTH wire-terminal bulbs used in switch machines and lock-onsand I have written up how to do it - but it's tedious and I don't recommend it!
I have to make one comment about red-green bi-color LEDs. Maybe you already have some that look good or were recommended by another train guy, but make sure the red and green colors (assuming that's what you using) are to your liking. Without getting into the nuts-and-bolts of LED semiconductor technology, you will find some red LEDs are more orange-ish than red...and some green LEDs are more yellow-ish than green. To each his own, but I prefer the deep red and deep green as you'd find in a street traffic signal. I've found that the green is more of a "problem" with cheaper LEDs often more lime-green than pure-green. Kind of like the discussion of using cool-white vs. warm-white LEDs for passenger car lighting. Again, to each his own...