IF you get a 560SEL or SEC engine then that should be a bolt-in that requires very few changes. Make sure that the 560SEL motor has exhaust manifolds & crossover pipe.

Yes, the timing chain & rails are a good idea. ALSO all of the "rubber" hoses & o-rings at the intake area should be checked & replaced.

ALSO take the oil subpan off & look at the oil pump chain & install a new o-ring on the oil level sensor connection.

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