Hmmm I must admit to never using it for headlights as it was classed as a trim dressing but seeing a post on another forum suggests it's the same stuff as c1,c5 etc so yeah should work.
Plenty of threads on dw showing c1 used on the lights but who knows which is best, @gm silo seal isn't a bad alternative not quite as durable and tough as the c1,c4 etc but much easier to apply. To throw this in also Exo v2 is a very good product which you could use on the lights, body work wheels,windows etc.