Ok. So I got it done! That thread really was great at walking you through the process. I had a few more bolts to remove on the passenger side than he showed, but after that it went well. I had to trim the new box as well to make it fit easier, then it went right in. After reassembly, I checked the system, and everything went where it was supposed to. Now I have heat on my feet, as well as the other areas!
Another point. Do not roughhouse the shifter cable out of the bracket under the dash or you could break the plastic sleeve and then it won't work at all. Ask me how I know....sigh.
All in all not too terrible of a job. It looks daunting, but if you follow the steps it, it goes well. It took me about three evenings after work, taking my time to get it done.I thought taking out the steering column would be a bear, but it was one of the easiest parts.