89mm, Yep that sounds pretty good to me, and so you use the panhard to control the degree of roll steer by changing roll centre heights.

I change the amount of roll steer by varying the torsional stiffness on the rear stabiliser (You say tomateoes I say tomartoes) : )
It still works the same

On the sunny you can improve the 4 link rear suspension dramatically by lowering the rear of the top arm by 22mm and lowering the front of the lower arm 22mm. This changes the rear arm angles into a tighter V, tightening the rear end up. The major benefit is a reduction in roll centre with a slight increase in roll steer.

With a panhard as well, its a good rear end to set up. Very predictable handling and excellent adhesion levels that allow good approach, mid corner and exit speeds. This is where small cars flog big bangers.



An easy way to tell if you have it right, is when cornering hard you can change the steering input to tighten up in a corner and the car will four wheel slide but very controllably and easily turn in tighter with a little throttle steer or go wide with the boot of carefully.
In the corner it will pick up the front first (feel it go a bit light) , then the rear wheel (gets lighter again and a bit twitchy). To keep drive at this point you need a locker, LSD or spool or you start the dreaded single spinner howl and chew your diff up. Its a bit like cornering a well set up Kart.