are three different ways to play Japanese Playstation games on the
foreign systems (US, Asia, European models...etc). One way is to
use swap trick which I personally don't recommend it. The second
and common way is to install the MOD chip inside the system. You
can buy the MOD chip from the internet, for example, Modchip.com.
In order to install this chip, you need to have some soldering skills
or seek help from a technical person. The latest and the safest way
now is to buy the device called PlugMod which it plugs onto the back of the system (Parellel I/O Port. This device
actually has some other neat functions, such as Game Shark codes compatibility.
The intended purpose of MOD chip and Enhancer are to aid in the
use of your Playstation to play imports that you legally own,
as is allowed by law.