Hey allen I own a 1993 500E, Im a factory tech for 14 yrs now. From my experience all 119 engines run a little on the warm side especially a big V-8 in a small compartment.
in Traffic shoould see the temp rise some times to a little above the 100 degree C. On highway you should see it at 80 or a little above. The t-stat is a rated open temp of 85 degree C. Tell me with a new radiator in bumper to bumper what does your get at? Have you had problems with your rear axle clunking. If so tell me what was the recomned repairs. Mines is clunking petty bad and all the hydronematic system is working to factory intent.
Look forward for your feedback.