1. Why would a LEO want a loaded gun handled in the first place, if I was a LEO and want someone disarmed it would be because I was afraid of them and if that was the case why not call for back up and make this a felony stop...? otherwise leave loaded guns alone, just my opinion.
2. If I am asked to disarm (which has never happend) I would agree with Abraham and "mention" the Glock is chambered and follow the officers directions.