While I offer no concrete proof - IIRC a 275 60 15 on a 15x8 wheel with 4.5" BS is the largest that fit properly in a STOCK wheel well application. I have a 95 Dakota project currently. I bought my tires. 29 15 15 Hoosier radials. I bought a kind of pricey tool that simulates any wheel for proper fitment and correct wheel purchase.


https://www.speedwaymotors.com/Wheel-Fitment-Tool-for-Tire-Fit-Testing-Size-Measuring-Mockup,485869.html?utm_medium=CSEGoogle&utm_source=CSE&utm_campaign=CSEGOOGLE&gclid=CjwKCAjwoqGnBhAcEiwAwK-OkbJzMGWZQCERpoljGSqCxLGyL2KdqnNirEvhHZPPuEy0wNpKZ3KniRoCslgQAvD_BwE