Use "Make Labels" to generate a TRCN

Having clicked the "Make Labels" button on a BCON (and bear with SimPE while it creates this resource - a pop-up window will tell you when it is finished) you can then open up the matching named and most importantly matching Instance numbered TRCN resource file to edit the labels. It will initially be populated with "Label n" but you can replace these strings with those of your own.

Editing Behaviour Constant Labels