In this fast track which lists potential changes for 1/1/2018.
It seems this does a couple of things. First it equalizes a Euro-spec E36 M3 with a Nissan Silvia due to the significant changes in those cars compared to the US spec. Second it seems to suggest that you can import and have a Toyota Supra RZ in this class if right-hand drive is considered to be a "comfort and convenience" allotment which seems to be the intent here.
After importing a Skyline (which will NOT be covered by this) I decided that i'm pretty much going to be importing all my future cars. I can get enthusiast cars with lower miles, much better condition, often even OEM, and cheaper than in the US. You can also get cars with rare options like slicktop MK3 Supras or MR2 Turbos which are far more common there. Also stuff that is extinct in the wild here like a ST185 Celica.
Now I am somewhat of a novice so I don't think about nationals or anything like that. Locally the modified class is mostly people with street cars that have engine swaps with 1 or 2 people who have serious builds for it. I "like" my local competition in that class.
It would be great if I could run a car like that with a JDM-spec engine that would otherwise be a legal mod in the class. This would covert a 180Sx for example. However I am under no illusion that this would legal from the wording there. Then you have the W20 MR2 which the difference is basically a tune.
If this change IS what I think it allows for I am happy, a few people aside me have been asking for it.