For those doing the conversion that will be using the stock fender liners and stock engine splash shield, you can just trim the liners a bit for the front Nismo bumper as follows:
Here is what they look like, kind of hard to see but you just cut a small notch so it slips behind the Nismo diffuser. I cut the notch like this |\ on passenger side and reverse on driver side. You'll see what I mean when you look at it.
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