You'll love the C2's - very nice midrange, very smooth treble. My advice - don't bother upgrading the 8" midbass speakers unless you plan to provide additional amplification. I swapped them with the Kicker/Shelby speakers and was not satisified due to the decreased bass output (single voice coil and require more power).
Thanks guys! Maybe I'll catch the bug and do some more upgrades later. This will be my first step and a fun project while I have some time of over the Christmas break.
Edit: Bought the C2's on Al & Ed's (read in another thread that this is a good site).
Was pricematched for 109 including shipping. (Less than Amazon with tax and shipping) http://www.al-eds.com/cart.php?mode=..._match=1793304
And got the Metra Harness here: http://www.ebay.com/itm/Metra-72-5600-Ford-Speaker-Harness-Pair-/360204958949?_trksid=p4340.m185&_trkparms=algo%3DS IC.NPJS%26its%3DI%26itu%3DUA%26otn%3D5%26pmod%3D28 0525756536%26ps%3D63%26clkid%3D4802298176002653322
DELIVERED: 2011 Mustang GT 5.0 Premium, Kona Blue, Black Leather Interior, HIDs, 3.73, Security, 19 inch Painted Aluminum Rims - Roush: Front Valance, Front/Side Splitters
Washington State 5.0 Owner's Thread: