Checkout Diffsonline. They give you options to configure the diff the way you want. I went with a Wavetrac and have been very happy with it. You can also elect to drop the final drive ratio if you are so inclined. Once you install the LSD you send them your stock unit in exchange for a core deposit. Really simple. Also, Turner Motorsport offers a similar service.
Edit: Checkout this post. Recommendations from a bunch of folks.
https://www.2addicts.com/forums/show....php?t=1390045