Ok peoples, got a chance to get a model 36 3 in. nickle made about 1973-74 the original box is blue not grey with correct label and all paperwork that matches gun? when did they stop using grey boxes for nickle guns?

According to what I have, the grey boxes were used for Nickel finished guns from 1957 to 1966. You must remember that different color boxes were sometimes mixed or used beyond the cut off date.