I bought one for my 90, along with the short shifter kit, and it rocked.
Since I'm a cheap bastard (cost effective), I have come up with a home Brew version that uses no clamps, and is a easy retro when you do a bushing swap.
Parts:
One and a half Pounds of fender washers. Large Diameter Internal hole.
2 wire ties
Roll of electrical tape.
Take of the shifter link, and slide the washers over the rod one at a time.
Center the mass, and one the edges apply a wire tie to keep them all together.
Cover with electrical tape to water proof.

Enjoy......add the missing linkz short shifter kit and ooooooh baby.