make the objects editable and apply the textures, then select the objects and do a Functions/Connect this gives you another object which is original objects joined with the textures on the right parts (the original bits don’t go away you can toss them or hide them whatever you prefer).
You could do it by Connecting the parts first then doing your own Selection tags to use with the textures but texturing first and Connecting means you don’t have to make the Selection tags yourself.