Hi, I just got a CS 54' Pickup and the spec sheet says the mid is 5.9k OHMs but on the meter it says 6.13K....Is that a big diff? Should I return the pickup?

Thanks and sorry if this is a silly question.
Don't worry about it. Every single pickup wound varies ever so slightly, and things like heat and cold will affect the rating. It's small enough that it won't affect the tone at all.