In the 540PP Japanese 90s seasonal event (and possibly the Japanese 90s Challenge in the National B segment of the Career Mode), a Toyota Supra RZ can appear, and it's (always) driven by U(kyo). Katayama
In Schwarzwald League, there is an AI driver who goes by the name of 'P. Rosso':
A few things to take from that driver listing:
'P. Rosso' is an Italian.
'P. Rosso' drives a Scirocco R.
The Mediterranean wind 'Scirocco' is also known as 'Ghibli' in Libyan Arabic.
The animation studio named after said wind, Studio Ghibli, released a film in 1992 about an Italian pilot, Porco Rosso.
Yes, we have a possible Ghibli film reference in a Gran Turismo game. Probably one of the least expected things I found while playing through Schwarzwald League a few years ago, but a rather nice and relatively little-known Easter egg nonetheless.