The shifter seat is located at the base of the transmission at the very end of the shifter. Unscrew your shift knobs too. You will need to remove all the trim parts to access the shifter boot. There are several bolts holding down the 2 shift boots to the body, remove those and pull the shift boot up and out of the way. You will see the shifter base plate and the second shift boot:
Pull up on the shifter boot to expose the lock ring. You will see two flat spots. Push down hard on these, one hand on each flat spot.
Rotate counterclockwise, and release. There will be the lockring, and a spring underneath. Pull everything up and out of the transmission.
What I found was the reminants of the old shifter seat. It was broken up in a million pieces.
After cleaning all the pieces out of the transmission and the shift lever, I was ready to re-install. Clean out all remnants of the old shifter seat. The shifter seat is a 2 piece bushing as seen here
The bottom black part was actually still inside the shifter base on my truck. I had to use a pic to remove it.
Install the new seat with the green side facing up toward you. Squeeze it in place, and it will drop right in. Now put the shift lever in the base and make sure the lever bends to the driver's side. It will fit the other way, but it will hit the dash when shifting. Put the lever in the base, put the spring on top, and now slide the lock ring over the pins in the housing. Push down firmly with both hands, and turn clockwise, and release. Slide your boot back over, and your done! Happy shifting!