Found some interesting info.
The YJ/TJ knuckle has a 10 degree inclination vs 12 degrees on the JK.
Can someone tell me what the XD60 inclination is?
Also what I found, it sounds like you want some positive scrub or negative scrub radius to keep from getting Squirm.
Squirm occurs when the scrub radius is at zero. When the pivot point is in the exact center of the tire footprint, this causes scrubbing action in opposite directions when the wheels are turned. Tire wear and some instability in corners is the result.
A positive scrub radius will allow the tire to rotate some when turned, you just don't want an excessively scrub radius.
I got to thinking about this because almost all of the scrub radius diagrams show a positive scrub radius where the 2 lines are at the bottom of the tire.