As much as I like this box I do have a question that's starting to play on my mind somewhat: Is this particular box the complex nightmare to work on it looks to be?
Christine, Instead of making a bigger PC board that can utilize the length and height of the box, the designers left the speaker compartment nearly empty and filled up the middle compartment with layers of PC boards completely covering the cassette section.
So one can see only the rear of the motor and nothing else from the back.
To answer your question I can say after some explorations to the unknown territory and taking pictures, belt replacement is not that hard as I expected.
One has to be extra careful in the disassembly process. The top two buttons cane be damaged if it is not pulled up, turned and locked in place. It is easy to break the tuner chord pulley posts and gang wheel. Ribbon wires can get damaged if one is not careful.
When the chassis goes in the front face of the box always keep an eye on aligning the counter reset button. It can get easily stuck without coming out of the hole. If that is the case the lower part of the chassis won't fit well. Never hold on to the handle because it can easily slide out from the slots.
Belt replacement is the only thing I did after some struggle and hiccups. Now it all became so easy for me to dismantle it and put it all back together.
One would would easily fall in love with the sound quality of this box. A little giant in every way!