Here's a pic of my CA-710 (a 610 II by anything but name as far as I can tell)...
The lamps look greener in the flesh.
They fit into little rubber cups in the main faceplate (not the dummy one you actually see), and in front of those are kinda triangular shaped pieces of clear plastic, used to disperse the light evenly across the width of the meter. These bits of clear plastic are held on only by being sandwiched between the main and dummy faceplates, and a set of four very small pegs moulded into them.