Here is the 4-link kit that I am looking at:

http://store.gaugemagazine.com/triangulated4-linkrearsuspension.aspx
http://www.ridetech.com/store/weld-in-air4link-triangulated.html

then again, I may simply design my own and sell along with my Crossmembers

The problems we face today can not be addressed at the same level of intelligence we were at when we created them - Albert Einstein Or with the same level of $ - Me