2/4 dr side skirts

Is there a big difference between the 2 dr and 4 dr side skirts for a 99 civic? The reason I ask is because I ordered a kit and I had it put on but they told me the side skirts are for a 2 door, but when I put them up to the side of my car is the length is the same as the stock sides. I would really hate to send them in for an exchange and find out they are the right ones lol. Any info is welcome, thanks!

the main differance would be the mounting tabs that usually mount over the lower door jamb and the curves to match the lines of the car

yeah because the tab need to be in different places so that they dont block operation of the doors. I think they should be the same length.