I've spent years tracking down kit parts for my RGV250 (VJ23) from Autorimessa/Racin Function in Japan, the company that built the official race kits for several Suzuki models but stuff for the GSXR400 is new to me. Over the years have you guys ever seen official kit stuff out of Japan or a race kit manual? I did stumble on a Japanese site where the guy had an Autorimessa pipe, CDI and air filter. I'm not heading to the track, just curious if anyone has ever seen kit stuff for the GSXR.

yes and made improvements to most the parts!

Yoshi did unofficial stuff for the early gsxr to the point of suzi using his frame design for the first ally model.
Ive a book by Yoshi with a kit list- forks/yokes,wheels,air box, loom,cdi + others and a F3 engine build.
I aim to pdf it and stick it up when time is allowing.

Cool, I'd love to see that.

The 2nd pic looks familiar, it will be intreasting to see more.