How do you change transmission fluid

There is no plug for drainage only one to refill which must be done on level ground or a hoist. the pan must be pulled to drain old fluid. if you have the ZF5hp transmission there is a filler plug at right rear of transmission. if a hydramatic it goes through the filler tube. THis guide will help walk you through the job

https://www.2carpros.com/articles/how-to-service-an-automatic-transmission

Check out the diagrams (Below). Please let us know what you find.