'97 XJ Wheel Arc diameter

Hello fellow Jeep owners, I am new to the forums and I come here with a question. The fenders on my '97 Cherokee Sport are starting to come apart and the bigger wheels aren't helping with the constant rub. Because getting aftermarket fenders such as bushwhacker where I live is difficult and expensive, I wanted to make my own similar to the flat bushwhackers.

The question I have is if anyone knows the lenth (cm or inches) of the inner arc of the tin where the fender clamps, not the lenth of the fender itself.

I will look for a picture of the part I am referring to.

Thanks for your help!