Then the sky is the limit. Or? maybe just get a few 7990 
I should have. I didn't do enough research before I bought these, so I didn't know it was basically 2 7970s put together. Maybe I'll just save up and get a 7990 instead of another 7970. My only concern is that the only 7990 I can find also has a locked voltage (which I think is source of my pain with the 7970s).
you talk about windforcce 3?
Yes.
You need a new case. I've got 2x of the same cards mining LTC (granted at like 1022 core 1244 mem for optimum khash) but have no issues keeping them below 80C and rock solid.
That I do not. I have the cards running in this beast: http://www.newegg.com/Product/Product.aspx?Item=N82E16811147157