Upgrade from 6.22 to 7.8 failed. All contributed modules was disabled or deleted using Uninstall, theme was Galland, all upgrade steps is done according to the UPGRADE.txt description. Upgrade ended with a fatal error. Now I restored the site to D6.22, but the database contains 125 tables - a mix of both Drupal 6.22 and 7.8 versions (I checked by phpMyAdmin).

After that I was installed Schema module and have report:

- Tables for which the schema and database agree - 68
- Tables for which the schema and database are different - 0
- Tables in the schema that are not present in the database - 0
- Extra or Tables in the database that are not present in the schema- 57(!)

Can I delete the "Extra" tables?

What the right way now? Fix the database manually?
Perhaps this is explained somewhere.
Thank you.