FWIW, it turns out you have to be a little more observant when linking channels. While the channels “match” the actual guides might not be for the located channels. You have to make sure the call letters actually match up.
In my case, channels 10.1-3 matched up, but they were for Grand Rapids and not from Lansing.
Long story short, my guide is better aligned with Battle Creek and not Grand Rapids – even though Plex matches me with Lansing from my zip code.
It would be great to be able to mix-and-match channels from different guides. FWIW, I have created a feature vote for this here:
Thank you for any votes and consideration. 
