Are there any tricks about getting the very small Phillips head screw out, that secures the knob for the trip meter? I've left it to soak with penetrating fluid (PB-Blaster) for several days. Also I've tried a heat gun. The screw is still in there tightly.
I recently restored a set of gauges and I removed this screw without much of a problem. I could see an issue with dissimilar metals corroding themselves together, as the screw is steel and the shaft it screws into is brass. The screw I removed, had green thread locker on it, but it came right out. Just make sure you use the right size screwdriver to get a good purchase.