Install the piece. Bilstein includes it for a reason.

Would you rather have the bumpstop impacting the seal area of the shock or the metal insert intended to take the load?

 

I think Ill just put the metal shim of the same size there for now. But today I was about to do shocks, took it to mechanic they took one out, and front top shock mount was all rusted out and they couldnt get the nut out. So now Im gonna have to find a pair of new ones . Anyone knows of a place where to get them please let me know. Im gonna start searching the forum as well.....

 

Auto parts stores and GM sell the shock mount.