welcome aboard. try using the search function in the upper right of your screen. try searching under "general", "performance" and "suspension" for your respective questions using "exhaust", "y-pipe", first mod", "lower", "springs" etc.
keep in mind the bassani is LOUD. the most popular lowering combo seems to be eibach+koni, but a lot of guys have the h&rs.
good luck! (wish i had 6k to spend on mods!)