GPS Odometer?

Ideas from Oppo on a GPS odometer? Gauges in the E28 work (speedo, tach, warning lights), but odometer doesn’t. I don’t so much care about mileage, as my title says “exempt”, but I’d like to know gas mileage as a general diagnostic.

I found a couple of things like this on amazon, but wanted to see if Oppo has other / better ideas?

https://smile.amazon.com/OZ-USA-Speedometer-Odometer-Battery-Motorcycle/dp/B01M3R85PR/ref=sr_1_4?crid=3BJGN13BZ37OX&keywords=gps+odometer&qid=1566758638&s=gateway&sprefix=gps+odo%2Caps%2C218&sr=8-4

https://smile.amazon.com/Universal-Speedometer-Odometer-KingNeed-C90/dp/B07MNC3WYB/ref=sr_1_8?keywords=gps+odometer&qid=1566759486&s=gateway&sr=8-8

I *could* fix the odometer, but that involves taking the dash off, which seems like a huge PITA just to get mileage.

Picture from the field at Minute Maid Park (home of the Astros) for your time. Work event on Thursday rented the center field suite, and with that you get onto the warning track during home batting practice. We had a limited area to roam, but it was still neat.