Hello: Duuoh I just realized I posted my query in the wrong forum. How do you open the listed machines without out cracking the housing ? Do they have tabs for release or do you just pry it apart and hope it survives?
Googled this. https://www.ifixit.com/Guide/Sony+Walkman+WM-AF48+Film+Revolver+Band+Replacement/30028 good luck
I had some good luck in starting the separation via a thin blade sharp knife and pushing in at one of the "claws" ( Sony's word not mine ) sections of the case. I placed a shim in the crack and worked around the split levering with a screwdriver and it came apart without too much trouble . One has some W/f after a belt replacement and the other is a tad off speed. Still learning and gathering information . On another machine I repaired a phone jack that had separated from the PC with the soldering iron and so far that is my best unit .