To support what Glen posted - that mini wedge bulb sitting in the mid console gives light to the fiber optic cable which illuminates the position indicator in the shift gate. I assume the reason for not having a bulb sitting on the shift lever, is that the lever can be moved back & forth pretty hard, and a bulb wouldn't survive that in the long term. What a delicate piece of engineering back from the early/mid '80s, which we might not see today.
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