A very good upgrade for the front axle is the 26mm swaybar from an ek4 or ek9. If you have a front swaybar in your ej9 then it is very simple swap. Nothing to change there. You only need the swaybar, the bigger bushings and the end links. With these you will be ready to go!
Here are some pics.

You can see the difference.
Here installed.

I can't tell you the effects of the bigger swaybar itself as i installed front and rear both, which is something i recommend you as well.
The overall balance is very great, reduced body roll, and very responsive steering.
Something you should know is that by installing bigger swaybars you tend to reduce the independence of the suspension up to a point. Still the overall positive effects outweigh some theoretical drawbacks.