different type of clock
they do come apart
think on 1994 models the 2 faces pull off (after removing the needles)
their are 3 diff types in total, all can be taken to bits as iv done it, the early ones like yours are the easiest to do as they dont use the rare chip leds to illuminate the 2 LCD screens, all you gotta do is remove the green filters from their aswell as alont the top and replace with led bulbs the colour of your chioce, white leds would work fine!, and i think for your type clocks you can buy the twist fit ones so no soldering needed even
pics would help, rear of clocks and front