Ordered the part, received it a week or so later (ordered late Friday, received 11 days later).
It worked perfectly! Once I put it in my backpack, I started the bike and, voila no low fuel light! My first thought was that proximity must be the case, but upon further testing, ie left the sensor in the backpack back at home, discovered that periodic absence works as well. Now I'm wondering how long the bike can be away from the spare part before the light comes back on.
I'll update my scientific results as the testing continues...