Faction & Illusions?

[Dr4z3r]

How do illusions currently affect race-based factions? Do illusions bring the person to a set level, or does it increase faction standing by a set number?

For example, by default if an Erudite with changes to a Dark Elf, Oggok guards will no longer be KoS. But if that person were to kill enough ogres, would the Oggok guards become KoS even with the illusion on? What about if they kill Ogres as a Dark Elf, and then try to walk in with Illusion: Troll/Ogre on?