Since you said "I thought that maybe, one or two of the connections was backwards and worked to reconnect everything."
I am guessing that you have the older Loop/Filiment type Glow Plugs. Otherwise I do not see what could get connected backwards.

If you do not put your year and model in your signature you will need to post that info each time you start a thread; or the answer you get may not match your question.

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84 300D, 82 Volvo 244Gl Diesel