Twin 70's are a little to large for only 1000 hp in a street car. Twin 50 s are good for about 1500 hp! You want to choose the smallest turbos that will do what you need to have maximum low end power. A 60-1 or 60-1 Hi-fi will be perfect. They are also VERY small. I am making about 900 hp right now with a baseline tune and pumpgas. The tubing is only 2" coldside and a 3" inlet!
This makes routing tubing very easy and compact.