I replaced the rack damper pin and am going to replace the motor mounts soon. Is it necessary to change the engine shocks too? How often do those go out?

Also, how much vibration do you all have at idle? When the cars were new, did they still vibrate? I can feet the seats vibrating slightly, and the passenger seat headrest vibrates visibly so. All 123's I've seen have been like this. Is it just old motor mounts/ engine shocks?