My coil's negative post has a wire that runs up and back, and then enters, along with 3 other wires, into a 4" housing. I assume from there it activates a dashboard gauge. So, it appears I have installed the coil backward. I will switch it, per your reply, so that the negative post will connect to the distributor.
Back to the nut--can I use the one nut that I do have, to do double duty, to hold that wire from the coil in place? Because again, I went to the Do-It-Center and bought an assortment of the nuts they sold. Nothing fit. They were close but no cigar.