I would guess they have to make it as a production car to enter it into classes of races. Similar to the Ford Escort Cosworth mk.5

Source: The Sun.
Was bat-boy riding on his back?

That is quite Old, Emanuel Yarbrough vs Daiju Takase in Pride 3. way back in summer 1998. he ended up going 1-2 and “retired”… goddamn size 21 shoe!