Aircooled VW South Africa

Hi all, I have this 1960's 6v/12v car radio. I find no info on the net, so hope some of you might have. I need to know the pin-outs of the rear 5 pin connector as I'm not sure where speaker or live wire goes. I know some of these old radios earthed on the chassis and some via the Arial but might be wrong. This radio does not seem to be stereo so could be one live, one earth and one each left or right speaker
Any suggestions?

As it is a duel voltage, I would think it would be 6v , 12V, earth, speaker plus, speaker neg.

Could also be the earth wire into the mount hole left back.

Think you would have to open it to confirm, as these old radios would blow for any miss connection.

Good luck

Herman