Jeff, is this retrofitable? or is it a complete display module?
It is feasible to do an upgrade, but it is a lot of work. It involves beefing up the power supply (Signal transformer, schottky rectifiers to reduce voltage drop, larger electrolytic), and the connector is changed to provide the extra pins for the backlight power. Then the LCD assembly itself is changed.
After doing the upgrade on one unit, I decided to set up the XTBM rental program, and give a $100 credit on a pre-assembled reflective XTBM toward the purchase of a backlit unit.