[Marshall V. Daut]

I agree with Robert/Texas: black. Black has its own special charm, as long as the wheels are kept clean and you have the authentic plated valve stem hardware. I would imagine the majority of Model T wire wheels were painted black in the day, as people back then were accustomed to seeing black wheels more than flashy colored ones.
Please excuse this comment on color taste, but in my opinion, ANY color you paint those wheels other than black will make your T look gaudy. Although your question is for a '26-27 Model T Touring, it's a kissing cousin to a '28-29 Phaeton aesthetically. To get an idea what black wheels might look like on your car, I am attaching two photos of our late '28 Phaeton, top up and top down.
Marshall