Fixture Offset on 20.5" Truss

[ChollyO]

I have a 40' length of 20.5" Truss that I want to stagger six fixtures across, three DS, three US but when I create the lighting position and hang fixtures they all lock into centerline down the length of the truss.  Is there a way that I can offset them easily so that they are centered under the chords?  How is the position that the fixtures lock to determined?

[Projx_CA]

Select the fixtures you want to move, then press the ~` (tilde) key and drag them to the chord you want.