Coil pack has no spark for cylinders one and four

Coil pack for #1 and # 4 has no spark. Replaced it, still no spark to plugs. Tested prongs at mount tabs and found 12 volts on one, none on the other, but so do the other 2 sets of prongs for the other 2 coil packs.
New plugs (.045) and wires, and the coil pack. Runs on 4 now instead of three. Long story.
Bottom line, where do these coil packs derive their power pulse? Why only those 2 cylinders? I put the "bad" one on another mount and it worked fine, did the same for the new one, it works as well, on any other set of cylinders. No spark at all for the pack at #1 and #4, first one on pass. Side. Help!
I'll gladly donate a tidy sum for the cause and repairs necessary.