Hello JHZR2
No fear, the job is simple.
I would replace the radiator and all rubber hoses on the car.
OEM brake Flex hoses have an average life of eight years.
OEM radiator and heater hose has an average life of ten years.
OEM radiator has an average life of ten years.
I think you should replace the hoses.
A day to replace all the cooling hoses, heater hoses and radiator.
If you drain the radiator there will still be coolant in the heater lines.
Burping air from the system is simple.

__________________
ASE Master Mechanic

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
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1985 300SD
1983 300D

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