Fenders

[Fairlady]

Yesterday I replaced my drivers side fender which had a huge rust spot on it. My car's an 86 and the fenders were off an 85. Anyway I noticed how they were different. My fenders roll out and has this flat crease and the one I put on just rolls out. You guys know what I'm talking about. Can someone fill me in?

Now I have to go find another fender! :x