RBR

I've got another question regarding the illumination of the front of the AM/FM/Cassette ICP. The right hand side of the panel close to the top seems dark. There must be a bulb burnt out. Has anyone attempted to replace the bulbs in one of these units? I tried taking it apart. There is many, many screws. I did manage to remove the 3 knobs, blower motor switch, potentiometer and the heater vacuum control switch. Also removed a tin plate from the backside of the radio. 5 more screws and unplugged some sort of a serial bus harness and then was able to seperate the cassette unit from the other unit. A few more screws had the front face plate off. A few more and 3 plastic stand off's that keep 2 circuit boards apart. Still can't see any bulbs yet? I'm pretty sure Ford doesn't even show the bulbs with a part #. I don't know if I should go any further, especially if its all for nothing, that is only to find out that the bulbs are part of a circuit board or something. Has anyone ever tempted this repair before?