pretty straight forward install
start by unscrewing the shift knob and then removing the boot/bezel by carefully pulling up to release the clips, watch out for the 2 locating pins in the front. I also removed the little storage tray under the ashtray to give me more room. This is done by removing the 2 screws at the base.
then remove the rubber and insulation on top of the assembly, two plastic caps hold it on.
next remove the metal plate holding everything down by removing the 4 bolts around the perimeter.

it will look like this

After that go under the car (need jackstands or a lift) and remove the nut at the front of the linkage that holds the lower stationary bar to the trans.
then remove the nut/bolt and disconnect the linkage from the shift rod on the trans.
(these two)

Then remove the 2 bolts holding the rear bushing on.

wiggle it all through the hole in top and slide the new one down and reverse the order

comparison between the two:
Baja is on the left, Sti is on the right (gold)

the sti linkage had the pivot point higher up on the shift lever. It also has urethane bushings on the pivot points and a harder rubber bushing in the rear. Also, the Bajas lever goes into a wider tube at the lower section which is filled with rubber. The STI lever is just a solid lever. Overall it makes for about 30% shorter travel, and a much tighter, less sloppy feel.
going back together with the new shift linkage.

Overall I think its a great improvement.