G'day TP - whilst I don't usually use EZline, I do use elastic to rig my bipes - I have had success with rigging before attaching the top wing as well as after attaching the top wing. I NEVER thread elastic completely through the wing - why? Because you don't have to

All you need to do is:
1. Small blob of CA at base of strut
2. Attach Rigging line, making sure it is shorter than the distance you want to span (ie so it will stretch and stay taught)
3. Small blob of CA at the base of the opposing strut
4. Wet the free end of the elastic line with superglue accellerator
5. Gently touch the end of the elastic line onto the blob of CA (the accellerator will almost instantly dry the blob of CA with your elastic line nicely embedded!).
'Tis as easy as that and means no messy painting of the wing once it is in position. Of course this method adds no structural strength to the model.
Hope this helps!
BC