If anyone was wondering, in order to use the slot for the rims on the Miura, you have to use the set combination for it's wheels. It's combinations, after looking in the Tire Database Viewer, are 54 and 144. 54 wouldn't load the rim and crashed my game, so be sure to use 144. What you do is you select that combination, then edit the dimensions of the wheel. After that, you can modify the name of the wheel and the file in the rims section of the editor. I figured this would be useful as Kamil said the Miura rims were sometimes buggy, so this is just a small tutorial on how to get past that.
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