Thanks to Ryan (@NeTitanXD) for the TSB document and part numbers.
Part 1: figuring out which parts to order.
Here is the link to the TSB. Included is the following parts list:

... I can now tell you that not all of these items are truly required to be bought from Nissan.
The above three items are the "STUD," "BOLT", and "CLIP" - and these are not needed from Nissan, necessarily... and here are the specs why:

"BOLT" = this is an M8x1.25 pitch SHCS, with red Loctite on the threads. Approximately 1" of threaded length. Easily sourced.
"STUD" = This is an M8x1.25 pitch (large) by M6x1.0 pitch (small side) steel stud. Large side is 1" threaded length, small side is just slightly more than 1/2" length.
"CLIP" = just a tiny zip tie. Nothing special about it.
So. The rest of the parts seem to be of solid quality, and I am actually pretty impressed with the included weather cap for the blades on the plug to keep it clean in transit. The replacement aluminum portion means this install will avoid the pain of both 1) trying to figure out how to plumb the heater in and 2) this will allow for significantly easier maintenance or replacement of these components if ever anything fails, due to being so easily reached.
Since it is 55 degrees outside, I will be doing the Part 2 -installation guide later this evening. I will get photos of each step and call out any tools needed or helpful for this task. Keep an eye out.
Part 1: figuring out which parts to order.
Here is the link to the TSB. Included is the following parts list:
Having just received my order today...OEM Nissan parts list said:

... I can now tell you that not all of these items are truly required to be bought from Nissan.
The above three items are the "STUD," "BOLT", and "CLIP" - and these are not needed from Nissan, necessarily... and here are the specs why:

"BOLT" = this is an M8x1.25 pitch SHCS, with red Loctite on the threads. Approximately 1" of threaded length. Easily sourced.
"STUD" = This is an M8x1.25 pitch (large) by M6x1.0 pitch (small side) steel stud. Large side is 1" threaded length, small side is just slightly more than 1/2" length.
"CLIP" = just a tiny zip tie. Nothing special about it.
So. The rest of the parts seem to be of solid quality, and I am actually pretty impressed with the included weather cap for the blades on the plug to keep it clean in transit. The replacement aluminum portion means this install will avoid the pain of both 1) trying to figure out how to plumb the heater in and 2) this will allow for significantly easier maintenance or replacement of these components if ever anything fails, due to being so easily reached.
Since it is 55 degrees outside, I will be doing the Part 2 -installation guide later this evening. I will get photos of each step and call out any tools needed or helpful for this task. Keep an eye out.