Difference between Retina Mid-2014 13" and Retina Early 2015 13" Top-Lid

theodore

New member
I found out about six months ago that the top-lid assembly for the 13" Retina Mid-2014 and 13" Retina Early 2015 are not interchangeable even though they look identical. However now I have a stack of these Top-Lids that I need to go through and they look identical. Does anyone have any experience with these and know how to spot the difference in manufacture year?
 
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