Hello all! So I recently inherited my dad's old stereo system. I want to get it up and running again. It was all in storage for about 20 years. I have cleaned the outside of the equipment and have used compressed air to blow out most of the loose dirt and debris. However, there is still a patina of gunk on the inside that does not blow off. I'm looking for recommendations on how I can efficiently clean this from the inside of the equipment.