The 1988 motor will work & fit w/o too much trouble.
The 1988 motor requires a HIGHER octane fuel due to higher compression.
The 1988 motor will require instlation of a pilot bearing for the manual trans.
You must use the flywheel from the 1986 car & the correct clutch for that car.
You can use the distributor & ignition system from the 1986 motor in the 1988 motor w/o any problem.

The oil pans are the same.

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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