If you use guidelines, place corresponding guidelines in the B file. Then delete the model in B, copy (Ctrl+C) the component in A and paste (Ctrl+V) it in B making sure you click on the intersection of the guidelines.
If you use guidelines, place corresponding guidelines in the B file. Then delete the model in B, copy (Ctrl+C) the component in A and paste (Ctrl+V) it in B making sure you click on the intersection of the guidelines.