Preorder bonuses
For being a simple PS2 port with some upgrades, the game did came out with some cool merchandise along with it, and believe it or not, those were preorder bonuses for it! (Yes, preorder bonuses have existed for way longer than one might rememeber)
Videogame
For preordering the game through Sega-Direct, which was an old site Sega hold so that people could buy the game they published in Japan (for example, GTA 3), one would get the following items:
Mobile holder
From what I can tell, this seems to be some kind of small keychain bag of some sorts? The form factor is aimed towards the flip phones of the era this was released, although the picture is so low resolution that it is very hard to make up how it looks exactly. Thankfully, somebody posted pictures of his unit, sealed though:
Course data collection
Ok, this one is pretty simple to understand, a leaflet where they give out the main technical details from each map, with the amount of distance of each circuit and sector. At least that's what we can guess from this, because as of today, there is not a single mention, nor picture of this preorder bonus on the entire internet. If I had to make an educated guess, it would probably look like the background image for when one is going to start a story mode mission.
Still though, the official guide for this game does also include this exact information, so it's not like we are missing on a ton here.
Steering wheel
For preordering the official steering wheel from Logitech (or Logicool in Japan), which was the GT Force that was released for Gran Turismo 3 but with the packaging rebranded.
Gumtape
For those who wanna recreate the Shingo battle in the story mode... well, now you can do it with an officially branded gumtape. That's about it. This is how it looks like in real life:
Black keychain
The other preorder bonus, which seems to be rarer than the former, is a simple black keychain with the AE86 car. In real life this is how it came to the buyer:
