Yes, you are correct in your information. MB did have a recall on those 603 motors with the trap installed. What they did was take the trap off and install a catalyst under the car. I think MB might still even honor this recall. Call your local dealer and see what they say. Those traps were notorious for sending little bits of themselves into the turbo and therefore burning up the engine and turbo. MB sure replaced alot of engines! Hope this helps.
'67 250SE Cabriolet
'93 300E 2.8