Pues no he intentado cambiar eso, pero talvez esta documentacion sirva

62bf - 00 = static title screen!
0x62cc - Pointer to Top of the Titlescreen GFX 2b*
0x62c1 - Pointer to Bottom of Titlescreen GFX 2b*
0x630c - Hoho X,Y (Inverted)
0x62d7 - Hoho Pointer to GFX 2b*
0x98616 - Titlescreen Arrangement
0x6381 - Top of Titlescreen Pallet map pointer 2b
0x6387 - Top of Titlescreen Pallet Colour - (01 - BGP01)
0x638c - Middle of Titlescreen (Gold Version text) Pallet map
pointer 2b
0x6392 - Middle of Titlescreen (Gold Version text) Pallet Colour
(03 - BGP03)
0x6397 - Bottom of Titlescreen Pallet map pointer 2b
0x639d - Bottom of Titlescreen Pallet Colour - (04 - BGP04)