steering rack bushing

What is the typical failure mode for these plastic bushings? I have the rack on the work bench and the boot removed. I don't see any pieces of the bushing but I do see what might be the bushing pushed further into the housing tube. Do the locating tabs break and the bushing just gets pushed...

The rack housing and rack gear cleaned up and painted. There is a needle bearing at the bottom of the pinion gear housing. The four semi-circles are where the pinion cover was staked to prevent it from coming un-done. The rack was clamped in the mill and each of the staked areas were cut away...