If you only added springs, you'll want to get a good set of after market shocks/struts like Koni STR.T to help deal with the different spring rates and height. The factory shocks aren't valved properly to deal with bumps on lowered springs.
FRPP HotRods Cams / American Racing Headers Long Tubes with catted X / Stang-Hi dyno tune
Saleen wheels / Steeda CAI / Corsa Xtremes, K Springs, Koni STR.Ts, UMI lca relo. Brackets/r lwr ctrl arms UMI adj. panhard bar / Camber plates / SR Strut Tower Brace.