For some time now, my reverse lights have been kinda intermittent. I had to push up on the shifter to get them to come on, and now they have went out. Checked fuses, wiring, bulbs, connector plate, all good. Unhooked plug which was in front of the trailer wires (closer to cab) and checked with a test light. Signals and tail lit test light, reverse didn't. Time to break out the service manual. Flippin through the diagnosis page, It says faulty or misaligned gear selector switch. I know it's on the column on my truck, but I ain't got the slightest clue on how to adjust it. It says to check if its faulty, get a test light and check the reverse light connection. Neither make the test light glow when its in reverse, but it says the dark blue wire's connector won't light if its faulty. So that leads me to believe it needs adjusting. So exactly how do I adjust it? Also, do yall think I'm going in the right direction or I missed something. Can't remember if its in my sig or not, but 89 GMC Sierra K1500, 350 turbo tranny.