How do you fit 20 inch rims on my 99 Cadillac sts?

To fit 20-inch rims on your 1999 Cadillac STS, you'll need to ensure that the bolt pattern, offset, and hub size of the new rims are compatible with your vehicle. Additionally, consider the overall tire size to avoid rubbing against the wheel wells or suspension components. You may need to make adjustments, such as using wheel spacers or modifying the suspension, to achieve the desired fit. It's advisable to consult with a professional to ensure safe and appropriate installation.