If you're going to do it, there's no "that'll do" concept. You need proper headlights, proper Evolution (black) tail lights, and everything else.
Someone a few days ago posted a thread in which he converted a new indus Corolla GLi into a US Spec XRS- including the engine, gearbox, and literally everything else included in a full-spec Corolla XRS.
THAT is a conversion- be it cosmetic or complete retrofit.
If you don't want to upgrade the engine, that's fine. But the cosmetics need to be matched to the Evo 100%