DUO2 ModChip Installation Diagrams:

US & PAL:

SCPH 3000X (V1/V2/V3)
GH004 020 no gap bios
GH005 020 no gap bios
GH006 020 no gap bios
GH006 020 gap bios (same as GH007 020 gap bios)
GH007 020 gap bios

SCPH 3X00X (V4)
V4 gap bios
V4 no gap bios

SCPH 3000XR (V5/V6)
V5/V6 Board

SCPH 3900X (V7/V8)
V7/V8 Board

SCPH 5000X (V9)
V9 Board

SCPH 5000X (V10)
V10 Board