The 1954/55 Chevrolet (Advance-Design) truck radio mounts on a plate that is attached to the radio.

The 1954/55 GMC (New Design) truck radio almost looks the same but (among other slight differences) its speaker has a mounting plate that mounts in the roof panel, just to the rear of the windshield.

I am not certain how the speaker wire is attached to the GMC radio. I have a 54/55 radio that has an RCA-type phone plug socket on the top of the radio for a speaker connection. This could be a GMC radio or a converted 1953/54 Chevrolet manual-tune automobile radio.

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