I kind of have the same project int he "planning" (dreaming??) stages. My current plans are to use a Dropmember C4 version (or the C5 version when it comes out) made by Nate at Porterbuilt Streetrods. He is on this site often in the suspension section. Here is a link to the C4 thread..
http://67-72chevytrucks.com/vboard/s...d.php?t=212001
I also am planning to stick with the stock style trailing arm suspension, but modify it like a NASCAR chassis. They use it on the road couse..
My planned ride height will be about 5-6" off the ground to the bottom of the frame. I might use airbags, take note of the cars that ART brings to the Goodguys shows and really performs at the autocross event.
just my thoughts.