from what I can gather, the only way the cop knows you have your pistol permit after running your plate is if its a cop from the town you reside in and originally got your permit in.
but yeah, when you hand a cop your permit they see it exactly the same way as if you were to randomly walk up to a cop and say only this: "I have a gun". and nothing more. they take it as a threat if you offer it without being asked for it.
when pulled over by a cop, the rules are very simple: most importantly, do not lie about anything (the only exception is if they ask you if you know why you were pulled over, in that case say NO, also never admit to how fast you were going if asked [if pulled over for speeding]); don't give them any info on anything unless asked; even when asked, you have the right to not say anything; never admit to a crime; never allow a search and/or seizure without a warrant; and never say or do anything that the cop could possibly see as some form of threat.
people underestimate the concept of rights vs common sense vs fear of hassle. IE: allowing your vehicle to be searched even if you know 100% there is absolutely nothing illegal in the vehicle. 3 things often happen when cops search your vehicle: they break a lot of stuff including parts of the vehicle, they throw everything around in the vehicle making the biggest mess possible, and yes cops do frame people in various ways quite often.
I personally allowed my vehicle to be searched twice. the first time I was 20, and they stole my case of beer and broke all my door panels ripping them off to see if I had anything hidden in the doors, they also were so messy in tossing stuff around that my registration blew away in the wind. the second time I was arrested for a huge list of things, all of which were bogus, and after 17 court trips the court saw it the same way and dropped everything. never again will I allow a search without a warrant.
