MySQL DB migration to WordPress DB

I have a website which a closed CMS that works with MySQL, and I would like to migrate as much information as possible from that database to a WordPress MySQL database in order to **migrate all content from the old website to the new WordPress version**. **The MySQL database has approximately 6000 posts**, and although there are similar tables/fields, there are others that won't be able to be migrated to WP, because they're too linked to the old design of the database, which has proven to be **too complex**. I've prepared a document **with equivalences between WP database structure (tables & fields) with our system structure (tracks & fields)**, and from that point I guess it could be possible to "rescue" posts, titles, tags and categories mainly. Please describe schematically your solution. All suggestions are welcomed. ## Deliverables The migration of the database will be paid depending on the quality of the migration. The most important is to migrate posts, tags, categories, authors and comments. There's other information relevant, but preserving the main content is mandatory. The content includes links to images that should work with a rellocation of the images and a simple "search&replace" to change the path on the content data. The WordPress permalinks should be the same as the current URLs generated by the current system, in order to avoid loss of SEO.