All of the annunciators in my aircraft have L:Var outputs. You can thank the developers Air Manager for encouraging me to do this. I don't list them all in the manual, because it would just be pages and pages of L:Vars. The name of the L:Var is the component name in the behaviors xml file, plus a prefix and postfix. For example, in the turbine aircraft, the fuel pressure annunciator "GSA_FuelPressure_L_EM" becomes...
(L:var_GSA_FuelPressure_L_EM_readonly, bool)
In the piston aircraft, it's...
(L:var_LeftFuelPressAnnun_EM_readonly, bool)
I hope this helps get you started. Let me know if you have any more questions.