I read on a retro radio site (not the company that retrofits old radios) that using a 4 ohm speaker on a radio designed for 8 ohm will harm the output transistor / amplifier.
My old radio guy (deceased) told me that these radios should be able to handle the ohm difference ok.
IIRC 67dart273 also indicated that also in a earlier post I have found. Thanks .
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