Most common mid-sixties OE type radio would have been the transistorized Becker Europa mono AM/FM. I have one of the two-piece (separate power/amp box) transistor Europas from a '64 220S, but unfortunately that radio is dead. Not sure what year the Europa switched to the one-piece chassis, but my Dad had the ultimate mid-sixties Becker in his '66 250SE. It was the transistorized 4-band Becker 'Grand-Prix', with AM/FM/Shortwave/Longwave and the signal seeking 'Wonder-bar' tuner.

Note: Early Fintails and probably coupes/cabrios used a narrower faceplate to fit in the contours of the dashboard trim. The radio knobs were also smaller than post-'67 models. Later (early'70s) chassis will fit in the hole but the faceplate is too fat and rides up over the upper wood panel and lower chrome strip. Currently in my '60 Fintail, I'm using an early '70s Europa, fitted with the faceplate and knobs from my DOA '64 Fintail Europa.

Happy Motoring, Mark

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DrDKW