If I’m Not mistaken, the numbered textures is caused from multiple materials. If you look at the materials you will see [Materialname].###. There will be a base material without the numbers usually. Go to preferences->Addons and enable material utilities. Then with mouse cursor in the 3D Viewport press Shift+Q->Specials->Merge Base Name. Then select the material base name.(The material without the numbers.) Click OK. You may have to do this with multiple material depending on how the materials are setup on the models. This will remove the numbered materials and replace them with the base. Note: The textures are inside the material. Now to clean everything up you can save and reload a few times or you can goto File->Clean up->Recursive Unused Data-Blocks. This will remove the unused materials along with the textures assigned to them.
