BTW I found an interesting nugget of info when I was looking up the PDC sticker on the R30 Silhouette. Google Translate can be a bit funky when it comes to Japanese, but I'm pretty sure I found a couple of references which said that the Nissan PDC sticker was a campaign to "Get Skyline Back To The Circuit".
Fans would buy the PDC stickers (which are available as repro now) for Y1000, and the cashola went into a fund to buy a new engine for the race team (or something). I'll look into it some more, but if anyone has any intel, please do share
I think you've got the gist of it there, Kev.
Basically, some of the motorsports-minded dealerships were lobbying the factory about getting more involved in racing the Skyline again. At the time, Nissan was still being quite reticent about this. They'd been concentrating on racing smaller - economy - models since the 'Oil Shock' hit, and this was the fallout, and indeed the sportiest of the R30 range wasn't exactly the most glamorous of Skylines for them to sell in comparison to the glories of past series. The dealers wanted a new homologation special to sell, and a new works Skyline race campaign for their sales to bask in the reflected glory of. The upshot was the R31 GTS-R homologation model, and - ultimately - the BNR32.
The Nissan PDC campaign carried on, and morphed into the 'PAss' campaign ( 'Prince Autosport dealers SponsorShip' ) which backed the works R32 GT-Rs that were entered for the 24hrs of Spa Francorchamps, and which did so well. Funny to think that it was the dealers, organising the general public at grass roots level, which succeeded in helping to bring the Skyline back to the track in works guise.