Questions regarding 1973 cars

[Max (SD)]

When did these cars begin having blacked out air vents and large bulky black bumperettes? Was it after a specific chassis number?

What does option code G01 refer to?

Thank you for your help.

[edmayo]

I'm not sure what you mean by air vents, the cowl vent has always been black, the horn grills became black in 73. The big bumper titties were D.O.T. required as of January 73 production, so there are 73 models produced in the latter couple months of 72 that don't have the big rubber ones. Most of those early cars came with the old chrome bumperettes, but painted black so they would look more like 73's.