Temperature gauge

Clean the rust off the posts threads. Try a standard 10-24 hex nut on there but don't force it or you could break the fiber board that the post is crimped into. It is pizz poor weak. That's why they used a weak nut. Seems there was very little quality control in the making of those posts. I've ran across a few that a real nut would not go on. I guess they knew the POS speedy nut would fit a less than perfect thread.