Took a chance and ordered some customizable 7 x 3 led screens off Amazon and I couldn’t be happier! You can change color, boldness, brightness, and tons of other stuff. It runs off 5v dc and no internet required but it does use Bluetooth to make changes. Best 25$ I ever spent though vs 600$ lol

Can you post a link to them?

IDK if this is the ones he has but seems like the same idea.

Amazon LED Sign

Another option

https://a.co/d/8m30lGG

They actually have them marked up to 40$ at the moment but I can vouch for these specific ones

There is a guy on Facebook putting these in an aluminum housing and selling them for $125 or $150 I believe. I thought I had it save but must have deleted it.

They come with some double sided tape and they’re made mainly for car windows anyway but I was thinking of making a little frame to mount them to in case they vibrate off. The only thing about wiring them is that they run on 5v, but you can just get something like this https://a.co/d/cLH0RLN . They store the program too though and have their own switch. So if you don’t change your dial you don’t need your phone. You can just switch them on or off as you please

nice share. Phone adjustment would have saved me from my steering cord snagging the adjustment last year headed into semis of $15k race. .000 R.T. to be .005 off my intended dial - instead I was accidently dialed up .01 and .003 behind for the loss.