Rear struts swap

Hello,

Those 2003 and 2006 Explorers uses different struts and are not interchangeable.

Here is a helpful guide of how to replace struts:

https://www.2carpros.com/articles/how-to-replace-a-suspension-strut-and-spring

I have attached diagrams for your reference.

Please let me know if you have any questions.
Thank you.