Following the procedure from the manual, the grilles come off.
Although I'm using the middle finger of my right hand for the 9 o'clock position.
Can't do it with my thumb, as Meridian suggests.

G61RSL, DSP7200, DSP5200HC
Lumin D2
Akai GX-620, Teac A-3300SX, Nakamichi CR-4A, CR-2A
Oppo BDP-103
Sony PS-X600, Nagaoka MP-110, Denon DL-103R
NuPrime STA-9, Elac BS 63
PS Audio PP10