I have those for my dart. Haven't finished the project yet because i'm still stripping theentire car down for paint. but I did alot of research and those springs are supoosed to raise it up in the rear and also provide great traction. good luck on your project. post pics when you're done installing them and i'm sure people will appreciate it!!
also, mancini racing was the cheapest place that I found to get the springs as well. although shipping is rediculous, it comes out cheaper than anywhere else.