MBs of that vintage came with either a Garrett or KKK turbo. The one in the picture with the beehive wastegate and metal boost signal line is a KKK. The more common Garrett has the wastegate sandwiched between the turbine housing and exhaust pipe flange, the actuator is bolted to the compressor housing and there's a rubber hose between the compressor outlet and actuator.

Sixto
87 300D

After hours of work on the exhaust the noisy motor is still there. The only thing left is the injection timing.