2004 Kia Optima alternator

It really isn't too hard. The worst part is how much room you will have to work in. Here are general directions not specific to your car, but will get you through the process. The only thing I can not stress enough is to make sure the battery is disconnected before you start working. Remove the ground wire first and do NOT cross anything that is an electrical conductor between the positive and negative battery posts.

https://www.2carpros.com/articles/how-to-replace-an-alternator

Let me know if you need help or further directions.