The H&R Super Sport springs, part # 51652-77 lowers a Mustang about 1.6 inches. These are great springs if you want a nice aggressive stance, but ALSO great handling performance. You will see on our spring rate chart
http://www.stangsuspension.com/store...tesarticle.asp, that the Super Sports have a nice firm, progressive spring rating.
Caster / Camber plates will be recommended if you want to correct the alignment after lowering. Remember, CC plates do not only correct alignment, but they replace your rubber strut mount bushings. What this means is a better controlled front end, better steering response, and more front end grip.
Your stock shocks/struts are completely worn (we can tell this just by the age of your Mustang). New shocks & struts will definitely be recommended.
Please let us know if you have any more questions...
Sincerely,