The two charging ports are different. Start at the end of the flex cable. The iphone 5 has a piece cut out to fit a screw. The iphone 5C is oblong with no piece cut out. Beneath the speaker. (The square silver thing) The two contact points on the 5 are on oposite sides of the cable. The 5C has them both together . Look at the headphone jack on the 5C it protrudes whereas the 5 headphone jack is flush and so won't fit. Lastly is the screw Tab at the side of the headphone jack. The 5 Tab is right near the front whereas the 5c tab is halfway back. Either way you wouldn't be able to screw it down and for each you would have a screw tab in the wrong place.
