Not sure but I would like to know as well, since I got raped by Ford today buying new lenses.
I have heard one thing though, if your going to use clear front turn signals it is best to use all clear from the same manafacturer or they will be off some. So from that I would guess there is some difference in all the lenses....
Has anybody gotten to see the repo besides the OEM?? I am betting that if you use two of the same it will look fine either way.
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1990 LX HATCH
My Homepage, outdated but some info valid