Accessory codes were not universal and varied by assembly plant. Generally only things that required specific changes to the body at the Fisher body plant were listed on the trim tag. Things like power windows, seat, rear antenna, tinted glass, padded dash, console etc. would be listed unless they were part of a specific model, ie., the console and shifter would be implied with the SS interior trimcode for bucket seats so would not likely be listed on the ACC codes although I have seen some tags with SS on them. A floor shifter in a Bel Air though would require a body mod so it would more likely show up as an ACC code.