I say just pick three twi'lek parts and reskin 'em, or reskin that twi'lek girl from the single player game, who is a full model (her name escapes me). Reskinning separate parts is nowhere near as hard as it sounds... heck, I figured out skinning for JO yesterday and this morning I was already making new parts for JA... pretty much the same process, and its cool cause you could easily enough make your twi'lek char a handful of custom outfits. And reskinning the full twi'lek model should be easy enough, exactly same thing you did for the Aayla Secura model.
Seriously, don't worry about reskinning the separate parts, its much easier than it sounds and as an added bonus, you can actualy use it in single player just as easily as in multi...they're one and the same. Just as long as you don't want selectable colors...those scare my chickens. My head still hurts from trying to figure those out...haven't given up quite yet, tho
Anyway, if you get stuck at any point, let me know email@example.com