Split Wheel sizes

I always thought that all the wheels had to be the same size.
I read the rules today again and any size can be used. My car came with 13s, so I can use 13 on the rear and 15s on the front??
Looks that way to me. Tell me where I'm wrong. please. TIA. MM

Use a different size on each corner if you like, as long as they meet the size requirements.

You can also run different rim widths as well. 15x7 lefts 13x5.5 right. Might be a good setup for Lime Rock.