New Ability Score Modifiers for Fortress Eibon D&D

In order to increase cross-compatibility with Red Box Vancouver, my Fortress Eibon megadungeon campaign is going to switch to using the Basic/Expert D&D ability score modifiers, as below:

3        -3
4-5     -2
6-8     -1
9-12   -
13-15 +1
16-17 +2
18      +3

Furthermore the Strength adjustments to hit and damage; and the Dexterity adjustments to Armor Class are now effective for all character classes and not just fighters.