Thanks for the replies. I'm using the Kodak E-6 kit but it looks like it wouldn't be wise to do what I had in mind. I wasn't necessarily trying to push or pull the film as much as I was thinking of manipulating things like acutance and contrast similar to the methods used for B+W film, but while still achieving the same color rendition. It sounds like doing so would throw off the color balance as you have all mentioned so I think I'll stick to the standard method for now.