Panasonic SA-HT650P Service Manual page 39

Step 7 : Rotate the hexagonal wrench in the direction of arrow, and then open the disc tray fully.
Step 8 : Release the both claws, and then draw the disc tray fully.
Step 9 : With forcing the left guide bar manually because the left guide bar interfers with claw,
draw the disc tray.
[Installation of the disc tray after replacement]