There are plenty of reviews out there of the Apollo - surely at least one has a pic with the bezel off. He helps those who help themselves (i.e. use their brains for more than just preventing their skulls from collapsing)..
Looks like the Apollo chassis is the same as the CM Centurion 534 et al. So the LED arrangement should be similar. Plenty of reviews of those out there as well. Uses the standard snap-in mounts for LEDs and switches. Not sure how the LED is held in the white plastic, snap-in holders as I've never had to fix one - but I'm fairly sure now that the LEDs themselves are standard round ones.
.bh.