there was a gen 5 gt4 light weight version. think it was only an import thing, JDM only option. have only ever heard of 2 in the uk and know one of them was scrapped. dont know what happened to the other. dont no what the designation for it was but it was a narrow body, no sun roof, manual windows, steel wheels and a few other things you only got on this one model.
i have a JDM only st183 hard top. it has manual gearbox, 4ws, a sun roof and super live sound system when it came out the factory. not come across allot of these in this spec level. most are auto's or verts or have no sun roof but are still rare in them selves.
also the cs/rc gt4 that was/is about (think owned goldspeed?? or something like that) that had factory spec paint in a gold colour. believe this is the only one in that colour (maybe in the world) and the vin plate to go with it. now thats rare.
thats all i can think of at the moment.