@CosmoKramer
Easiest way is probably by editing 'pedaccuracy.meta'
...\mods\update\update.rpf\common\data\ai\pedaccuracy.meta
It's basically the global accuracy file. Vanilla looks like this:
<?xml version="1.0" encoding="UTF-8"?>
<sPedAccuracyModifiers>
<PLAYER_RECOIL_MODIFIER_MIN value="0.800000" />
<PLAYER_RECOIL_MODIFIER_MAX value="1.000000" />
<PLAYER_RECOIL_CROUCHED_MODIFIER value="0.500000" />
<PLAYER_BLIND_FIRE_MODIFIER_MIN value="2.00000" />
<PLAYER_BLIND_FIRE_MODIFIER_MAX value="4.000000" />
<PLAYER_RECENTLY_DAMAGED_MODIFIER value="0.300000" />
<AI_GLOBAL_MODIFIER value="2.000000" />
<AI_TARGET_IN_COMBAT_ROLL_MODIFIER value="0.200000" />
<AI_TARGET_COMING_OUT_OF_COVER_MODIFIER value="0.400000" />
<AI_TARGET_IN_COVER_MODIFIER value="0.400000" />
<AI_TARGET_WALKING_MODIFIER value="0.6" />
<AI_TARGET_RUNNING_MODIFIER value="0.3" />
<AI_TARGET_IN_AIR_MODIFIER value="0.3" />
<AI_TARGET_DRIVING_AT_SPEED_MODIFIER value="0.3" />
<AI_BLIND_FIRE_MODIFIER value="0.3" />
<AI_DISTANCE_FOR_MAX_ACCURACY_BOOST value="5.000000" />
<AI_DISTANCE_FOR_MIN_ACCURACY_BOOST value="15.000000" />
<AI_HURT_ON_GROUND_MODIFIER value="0.10000" />
<AI_HURT_MODIFIER value="0.5" />
<AI_PROFESSIONAL_PISTOL_VS_AI_MODIFIER value="2.500000" />
</sPedAccuracyModifiers>
To start with, try editing:
<AI_GLOBAL_MODIFIER value="2.000000" />
I think higher values of '<AI_GLOBAL_MODIFIER' make the AI more accurate, but a quick test will confirm