You can try setting the line-height to 1.2 to try to get KF8 to match KFX. However, if you are trying to get KFX to match KF8, it cannot be done.
Do so in the CSS with body.
Code:
body {
widows: 1;
orphans: 1;
margin-top: 0;
margin-right: 0;
margin-bottom: 0;
margin-left: 0;
text-align: justify;
line-height: 1.2;
}
This is the body code I use except for the line-height.