Hi,I never seen Turbo30 in realife but normally the backlight of character LCD is integrated part of the LCD module itself. So if it's not already have the backlight built-in then it's not easy (or practically impossible) to install the backlight into the LCD module. However you can replace the LCD module with the one that already have the backlight built-in. Most character LCD module are generally compatible. It will cost you around $10-$20.
BTW it's possible that the old LCD in Turbo30 may already have the backlight built-in but CE doesn't used it. Normally the PCB pads of the backlight are on the right side if you look at it from the front. They are labled A and K. The LCD that have backlight built-in will have 2 little white pads with solder dot installed over it. If it's just plain copper pads with hole then it doesn't have backlight built-in. The attached image is the LCD with backlight.
Maybe someone with Turbo30 could give you better advice.