Nissan trucks are assembled all over the world. They can be assembled in Mexico and in Canada. On the other hand, they can also be assembled in the United States.

nucleolus

They are assembled in cytoplasm.They are made in nucleolus

Redundancy is a characteristic of usage, not of words. It would be possible to use the word assembled in a redundant way, for example, the assembled structure was built by a skilled crew. Since it was built, it was assembled; you don't have to say it twice. However, you can also use the word assembled appropriately. I assembled my forces.

The past participle of "assemble" is "assembled."