lowered

So I'm about to pull the trigger and purchase Eibach Sportlines for my EB,only problem is the fact I'm new to the world of lowering cars/suspension in general. If I buy these, what all else is needed for this? Or am I good to go with just changing the springs? Please, someone shed some light on...

Should be a simple question for some people to answer. If I'm currently sitting on 18" wheels with stock tires, what springs would give me the lowest overall drop without rubbing? So far I'm seeing only about 1.25" and 1" using Steedas progressives, but I feel like I'd still have a large wheel...