My son and I just got his grandfather’s old Nagra iii up and running and got it to record and play back. We were so exited we wanted to improve the sound by cleaning the commutator/brushes. Well, we blew it and ended up damaging or putting the brushes back wrong because it stopped working. Does anyone know if the brushes and springs are available for this unit? Or did we just ruin this Nagra? We are so disappointed that we made this mistake and are looking for any guidance we can find. Thank you for any suggestions.