You need to add more detail to the front of the headlight tube so that it's a little rounder. Cut in the edges shown in green all aorund the light and then adjust to give some rounding to the tube. Chamfer the edges shown in light blue. Experiment with chamfer values till you have something that works for you. Toss a Symmetry and a MeshSmooth on it.
Next is the reflector inside the headlight. Create an 8 sided cylinder with three or four cap segments that can fit inside the headlight tube you just finished. Delete all the polys except the top cap polys.
Now select the rings of edges and move them inwards to get a nice bowl shape. Now position it inside the headlight tube. Add a symmetry and meshsmooth.
Create a small sphere and select the polys shown and extrude them outwards. Do some tweaking to get a nice lightbulb shape.