i have 245/45/17 tires...and going to install eibach prokit lowering springs and sway bars..hopefully i won't scrape on some speed bumps or exits...

 

The 245/45/17's is:
(24.5cm) * (1/2.54 inches/cm) * 45% * 2 + 17inches = 25.7" diameter
which is more of a 2004 & earlier tire size. Since our V6 Mustangs have a stock 27.0" tire, you are already:
(27.0" - 25.7") / 2 = 0.7" lower than stock.
You might have a ground clearance issue when adding the Pro-kit.