I bet you pondered over those spare bits for hours trying to work out where they might have come from....lol. The original tail lights must have been fitted to a few of the European destined C31's as they come up on ebay occasionally.
I see that your factory "2.4" badge has survived and put back on in pretty much its original position, so the reason for the tail light/garnish change cant have been too serious. Personally id either leave it as it is, or maybe just paint the garnish part body colour like it would have been when new.
If I remember correctly these were $23,010 when they were new, and a 910 ZXE Bluebird was $17,017 in 1982. Incidentally a 260C Brougham was $17,000 in 1980. I bought mine in about 1995 or so and paid $6995 from a car yard. I was amused by the fact that as a "luxury" car it still had a manually operated choke. I always had issues in winter with the carb freezing and stalling at every intersection on the way to work, and there was no summer/winter setting on the air cleaner horn or associated equipment to stop that happening. The other thing I remember was how incredibly over assisted the steering was. You could almost spin the steering wheel when stopped with one finger, and it was like that all the time, not speed sensitive like the C32's are. A guy I knew that had one the same as yours but that orange/red colour, said when he replaced the rear shocks, he used 280ZX ones as they have the same size holder that the spring sits in, as the import C31's have smaller diameter springs. I only found that out after I had already replaced mine with factory Nissan shocks, as the 2 different aftermarket brand shocks I tried had too small spring holders. His also had an economy light on the dash that flashed when you stomped on the accelerator warning that you weren't driving economically. My handbook showed it, and from memory it looked similar to the warning light for the manual choke. The facelift C31's only had a blank spot instead

. And the L24S engine doesn't need a mention, we all know how good they are. NZ C32 2.4GL sedans have the same single carb engine.
Enough rambling, have a head full of trivial stuff like this...lol. Will dig out the Motor World, not sure if its here or at my parents place. Also found a factory C31 workshop manual, that I forgot I had which you are welcome to have. Was given it when I had mine.
Found this, a close up random pic (from a "cars in movies" website) of what yours would have looked like at the back. Pre-facelift C31's had the number plate lights in the bumper, where facelift ones had lights either side of the number plate.
picture share
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