Before or After
Bob,
The lighting kit is designed so the lighting kit can be installed during or after wing construction. Of course, during construction would be ideal. The big thing to remember if planning to install the lights after the wings are completed ? make sure you install a pull cord through the grommets so the wires can be pulled in later.
If you are NOT building your RV-12 as E-LSA, you may also want to consider using shielded wire for the strobe wiring (suggested by AeroLEDs). If you go that way, consider using a larger grommet in the ribs for easier install of the wire. I used 7/16? SB-437-5 grommets and ran shielded wire for both the strobe and landing lights because I wanted wig-wag as well and felt shielded wire may be helpful there too.
Happy Building,