I just finished a 4 link, lower links are at 35", upper links at 26.75"
Runs great down the road, haven't had it out on the trails yet. But it soaks up the bumps zipping across the field without a problem.
We used the 4-link calculator from the eXtremem Off-Road website and information from a 4 Wheel Off-Road article on designing your own 4-link for the recommended lengths of the top vs bottom and such.
One major change we did over standard convention was to mount the upper links along side the frame rails. This was a maximize ground clearance but did increase the roll steer. Talking to others as long as you keep it below 7% you should be fine. We are around 5% depending on the link setup we use.
http://www.zukiworld.com/forum/index.php?topic=24382.0