This is absolutely the best thing you can do for your drive. Installation was straight forward, although i had to make two mods to complete: the shift arm shims needed to be shaved down on the inside a hair in order to allow the shift arm extension to fit over the original shifter shaft - no problem for my dremel and oxide bit. the second was to gain access to the top of the bolts that hold the tower in place in order to add the aluminum riser. LCEperformance techs recommended that I lower the transmission from the rear motor mount to gain access to the transmission tower from the underside, but instead I just used a step drill bit and removed four 3/4" holes above the four rearmost bolts in the transmission tunnel, and removed the bolts through the holes from above. After replacing the spacer and tower, i used 3/4" metal hole plugs to, well, plug the holes with metal. In conclusion, it took 0 time to break in, although some enthusiasts here have mentioned it might, and it now smoothly and quickly shifts through all gears. There is no longer a loose and wobbly play when in neutral, and the action is firm when seated in gear. It is a pleasure to row the gears, and couldn't be happier!
There are a couple companies making them but lce is the only one that I know for sure that makes one for the W55.