As the factory 12AT was only released in Japan I assume that there was a lot of aftermarket tuning done on them by Japanese workshops?

Any of you guys in Japan give me an idea of a typical setup or what was a typical setup?

Some of them have been imported to Oz. Here a typical setup is to bolt on the 13B turbo using a custom manifold and use the stock 13BT IC. There are even adaptors to allow the 13B inlet manifold to bolt on so u get your extra 2 injectors.

cheers