Compressor Field coil back doesn't match replacement
 

I've got a 2009 honda fit sport. So I bought an AC compressor off of Rock Auto just for, hopefully, the clutch, pulley, and coil. I took everything off the new part and got everything off the car BUT the field coil back had a notch on the replacement and the old one has dimples. I don't freaking understand how they could be different but there you have it. Is this an irrelevant issue for installation? If I can get it to lay flush is it fine? I'm kind of distraught since this is the first time something from Rock Auto has been weird.


https://cimg3.ibsrv.net/gimg/www.fit...60a747ed75.jpg