Is the fuel-filler nozzle diameter used in Japan(which safeguards against using leaded fuel in vehicles fitted with a catalytic converter) the same as the U.S? Or are they converted when Skylines are imported?

Is the fuel-filler nozzle diameter used in Japan(which safeguards against using leaded fuel in vehicles fitted with a catalytic converter) the same as the U.S? Or are they converted when Skylines are imported?
on my skyline it has a full size (or whatever you want to call it) fuel nozzel and on our k-car it has a smaller diameter one that the nozzels on base JUST fit in so it's not the same size for every car in japan. You should not have a problem with a skyline in the states though, we use the same pumps here on the military bases (I think). Hope it helps.

The Skylines and most JDM Spec cars don't have the smaller unleaded fuel neck. I don't recall seeing it listed as one of the conversion items on the US legalization petitions, so it may not be required for the US legalized conversion.

I know it is a requirement in the UK for it to be imported. Here's a site that has an easy fix available:
http://importsolutions.co.uk/fuel_neck.asp