flicker filter

Hi
Is there a way to hack ps2 games that they will not use the flicker filter
Some games let you set this(tekken 4,5, final fantasy 12, some 2d fighters) early ps2 didn't use this. I like the clear look of games when they are running without flicker filter
If somebody can point me to right directions i will gadly try to hack the games myself(what i mean is that i will try to look at the elf files to see whta has to be modified) i think a goos start would be to look to those games that lets you change the flicker filter option and to see what's happening when you set on/off
thx