Exchange 5 speed overdrive gear box 260/5.15-TNW for 325iC (C=Convertible) up to 12/1987 only manual gear box with cat, you need 1 for 1 car and for 325iC (C=Convertible) up to 12/1987 only manual gear box without cat, you need 1 for 1 car and for 325iC (C=Convertible) from 12/1987 up only manual gear box, you need 1 for 1 car
Exchange 5 speed sport gearbox 260/5.50-TNN for 325iC (C=Convertible) up to 12/1986 only manual gear box with cat, you need 1 for 1 car and for 325iC (C=Convertible) up to 12/1986 only manual gear box without cat, you need 1 for 1 car and for 325iC (C=Convertible) from 12/1986 up to 06/1988 only manual gear box, you need 1 for 1 car