Suggestion: Call the parts departments of the Chevrolet dealers in your (that?) area... and ask for *Parts department*, and ask to speak to the 'oldest/longest term' employee.... Find out what their current 'zone' and 'dealer' numbers are and when the last time the zone/dealer number changed. They *might* remember the older zone and dealer numbers... Zone numbers change in a 'wholesale way' (for all the dealers in that service region) whenever Chevys Parts Distribution Warehouse change locations (from one city to another); the dealer numbers change when there is a change in ownership of the dealer.. So over 47 yrs, both of these can change many times even though the actual dealership never moved... In my case, the zone number changed 3 or 4 times since 1969 as the 'parts distribution warehouse' moved from Birmingham, to Atlanta, to Jackson, MS and finally to Dallas... and it may have moved again since I last checked all this. I was able to find a parts man (an old friend) who remembered the prior zones as GM moved their parts dist warehouse locations...
