I am not real familiar with the 124 chassis. However, the front end "clunk" on my 126 chassis turned out to be guide rod mounts.

I found that the vibration of worn guide rod mounts " clunk" and can really be felt with your feet (due to location)especially when going over something like a speed control bump.

However, a "clack" noise, that you can hear but not feel much while driving over small road variations, turned out to be sway bar bushings.

Hope that helps you narrow it down for you.

__________________
Sam

84 300SD 350K+ miles ( Blue Belle )