I have modded a few ps1's but i don't think i have ever modded the 9002 series? I guess that was the later revision that lacked the rear I/O parallel port?
I have only ever used the 4 wire chips and always soldered them to the underside of the motherboard..... Can't say i have ever encountered any problems playing NTSC games over RF or Scart and both Dino Crisis games run fine on mine
I have no idea what source code was used in these chips, i got mine from a friend years ago who worked for a small video game store where they also used to repair and mod consoles.
As i said i have only ever used the 4-wire mod chips and have had no problems at all so what is the difference between these and the 3-wire versions?