The bushing on mine is where a torsion spring is mounted to the pedal assembly. In order to replace it you need to pull the entire clutch pedal assembly out of the vehicle and place it in a vise to release the tension on the mount.

Fortunately I found a thread on another forum that identified this torsion spring as a change that was implemented in the generation 3 4Runners. Apparently the older generations used a normal pedal return spring, but Toyota decided that the could use the torsion spring and make the clutch easier to depress. Unfortunately they used a small plastic bushing (horseshoe shaped ) where the pedal rotates on the spring. The other thread also identified that the mount points for the older style return spring are still in place and that it is a simple task to remove the torsion spring and replace it with the older style return spring.

So this weekend out comes the torsion spring and in goes the old style one. No more bushings.