My son has a 2003 GT Mustang. About a year ago he installed a white face cluster panel. Everything worked fine. Now, one year later, the two gauges on the right side don't light up. All the other gauges do, just the two on the right that don't. The gauges work fine, they just don't light up when the lights are turned on. Is this repairable? Are their led bulbs or something that I need to replace? Never worked with this, so I have no idea how it works. Thank you for your support, Tommy.