Small update..
Here's how the rectangular switches will be 'capped':
I got me a mini USB keyboard with keys in sat dimensions for this. A key will be adhered on top of each switch, after it is painted, and covered with a laminated tag. Once the key is ready, it will be spray-lacquered before being secured.
For each key to sit properly on top of a switch, some dremellin' has to be done. Keys have a shape that helps them to snap on the keyboard, which has to go.
Here's how a key is underneath before i removed the excessive plastic:
...and after:
It might not look pretty, but it will not be visible!
Here's the key painted white, and carrying the appropriate tag on top:
Finally, a couple of pics with the panel showing how the keys look:
Now, remember, these are not glued yet in place, and the panel's fascia is the temporary one, for experimentation only!