I'm putting an LS1 in a Cobra as well. Very light & powerful motor, with all of the 1990s/2000 technology. Using a B&B kit, and running a 6 speed transmission.
Here's some directories of pics (more to follow)
http://www.chitownsyty.com/bg/cobra102801/
http://www.chitownsyty.com/bg/cobra110401/
I'd be interested to see any pictures of LS1 installations in Cobras, to see how they have dealt with issues I am encountering (headers/engine mounts/6 speed/clutch).
Fred Green
GM fan