I'm in the process of researching how big I should make my wheels spats and where to place them. As I've been driving, I've been looking at cars driving by and seeing who has what. And surprise, surprise, 99.9% of them are NOT American vehicles. Imagine that... Anyway, I see some that face straight down, some that are angled forward a little, and some that are angled back towards the wheels some. I even see some that are mounted 4-5" before the wheel wells (mainly on BMW), while most are flush with the wheel well liner itself.
So post up some pics of your front and rear spats, whether they be stock or home brewed!