Playstation PSIO Fitting

The PSIO cart needs a small mod fitting to the Playstation main board in order to intercept several signals which are not present on the parallel port.

My recently acquired Playstation is a SCPH-5552 and has a PU-18 model mainboard.

Install instructions: pu-18_r13.zip

My install; some pretty small traces there to work with, that's pretty much at the limit of my ability (and tools, and eyesight!):