With all the interesting things done, this is just the first couple steps in reverse.

Collect cleaned contacts and nuts

Make sure the battery pack is securely fastened together

Pop the plastic covers back on the bus bar and the vent tubes on the top
And we’re all done! Battery pack fixed, balanced, reassembled and ready to go! Putting the battery back in the Prius is exactly the opposite of taking it out. Screw in a bunch of stuff, try not to break anything or strip anything. I didn’t put it back together though, on the off chance I would have to take it out again…
One last note
I put the battery pack in, crossed my fingers, and turned the Prius on. Everything went terribly. The dash lit up like a Christmas tree. My heart sank; this had been an almost month long experiment of stress and an intimidating amount of learning. In an effort to not curl up in a ball and lay there for a while, I turned the Prius off and tried the only thing that was left: wiggle the safety plug. I had read that it was a bit tricky to set it in properly. I had taken extra care to make sure it sat properly. I had screwed it up though! Holy jumpin’, I tried not to get too excited with another shot. I took the plug out, pushed it back in, then repeated a couple times. Finally it sat in really securely – once clipped in it didn’t wiggle at all.
Crossed my fingers and my toes this time, pressed the power button and… success! No lights anywhere! Glorious lack of abject failure. I took the car for a quick drive, everything went as well as could be expected, and I parked it for the night. So if you’re in the same situation – double and triple check that the safety plug is seated correctly before having a stress breakdown. And then probably take it out and try all over again, because it’s not exceedingly easy to sit it in perfectly. Good luck!