There are several companies to choose from.
I am installing the Griggs one myself:
http://members.mustangworks.com/drudis/
This is for roadrace duties, and moves the geometry around, so you gotta be ready for that.
If you go with D&D or other ones, those are more bolt-on type.
READ THE MUSTANGWORKS TECH ARTICLES. Rudy wrote a HUGE K-install article with photos and everything!!!
------------------
Darius Rudis
Roadracer: Home built t-arm/panhard suspension powered by an S-trimmed motor :-)
My Mustang Page