Where to find...
 

We seem to be missing a front 'trim' piece. Below are 2 pics. I was thinking I need to replace it before I can renew our brake tag, since the wires are hanging, but the other side doesn't light up regardless of headlight, parking light or turn signal use (both round white signals facing front work).

What function does the cut wiring serve?

For future reference, what is the part called, and where might on find it?

Thanks!