Projector headlights for your car would look something like this:
or
You'll notice that projects use a spherical like glass ball that the light is shined into, and then focused in a narrow, but strong path. This helps light up the road. It also gives off weird colors at different angles... converting your stock housing to projectors is pretty much impossible, unless you JB Welded some (projector) fog lamps into the housing. That would be ghetto rigged from hell.
-Ducky