The easiest way to implement backlighting on an M would be using EL mat or panels. You would just need to cut holes to match up with the barrel plate, set it down, wire it up, turn on, and admire. That being said, EL panels do get on the pricey side for something of that size. I have seen that some places will cut EL panels to sized including holes, that would probably be the best bet, however would be the most expensive.