If you are going with the 28" on back, what people are saying is that a 27" front tire is better, filling up the front wheel well like the 28s in back, and providing a slight rake.
With the 26" in front, there will be a big rake to it, I have this on one of my cars. With the 27" there will be less of that rake and it really looks better filling up the front wheel well, I think. I don't have too good of pics on my website, but the top pic is the 28" rear, 26" front, and the bottom pic of the 86 is 28" rear, 27" front.
I just posted on a couple threads about this and using a 4" front wheel, see these threads:
I already have 235/60's on the front 275'60 on the back and I like how they look. I was just thinking of the 225/60's because there are a lot more tire choices around in that size.