Update Opencart sites from 1.5 to 3.X

I am looking for a skilled developer to update my Opencart sites from version 1.5 to version 3.X. Here are the requirements for the project:

This is not an easy task because the database has been changed from 1.5 to 3.X so I know it could give some complications. But for someone that is an expert in this matter it should be no issue. I have 3 websites that have to be updated all of them are different but need an upgrade from 1.5 to 3.X

Backup:
- I have a current backup of my Opencart site.

Customizations and Extensions:
- I'm not sure if there are any specific customizations or extensions on my current site that need to be preserved during the update. The developer will need to analyze and determine this.

Timeline:
- The desired timeline for the update is as soon as possible.

Ideal Skills and Experience:
- Experience with Opencart and knowledge of the differences between version 1.5 and 3.X.
- Proficiency in PHP, MySQL, and HTML/CSS.
- Ability to analyze and determine if any customizations or extensions need to be preserved during the update.
- Attention to detail and ability to troubleshoot and fix any issues that may arise during the update process.

If you have the skills and experience required for this project, please submit your proposal.