Agree with Bomber here.
If they are off a 99 Grand they will be 16x7", so too small to clear the Commander front brake calipers, plus they will also have an offset of 50.8mm, which means that they will sit 7mm closer to the body of the car than standard Commander wheels which are 17x7.5" with a 43.8mm offset.
Given that you would need to run spacers no matter what, it's probably best to stick with the original Commander rims.
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