Changed engine ground wire, no power. 02 DTS

So I had some issues with my dash doing crazy things, things turning off while driving. Discovered that in addition to a new battery, I needed a new engine ground wire. Replaced those both, now I have no power to the dash/ignition. Bolts to the ground wire are both tight and so is the battery. To test I had ground, I used a jumper pack from pos jump point on the front fuse box to the strut bolt, where I've always jumped from. With the broken ground wire, it would not work at all unless I hooked ground to the engine directly. Now it has strong connection and sparks when jumping, but the ignition has no power without the jumper. When the wire was broken, the dash would at least come on and read some voltage. The only thing different between that and this is I have the radiator fans both unhooked so I can make sure everything is good before I put everything back together. Anyone have any idea why the power is not going from the rear battery area to the front?