I think Taco Johns started showing up in the Quad Cities (Rock Island, Moline IL, and Davenport, Bettendorf IA) in the 80s or 90s.
My family ate there a few times. And yes, I agree the food was better than TB. I think I recall a flat hard shell ‘cinnamon taco’.
Haven’t been to one in at least 15 years I suppose.
The flat fried cinnamon taco with an apple spread was a Taco Grande, which was tasty, but they don’t sell anymore. TJs is a Wyoming company, which I thought had surprisingly good Mexican food while on a visit out there. They just opened a store in Kenosha.