DriversFound.com: Scirocco Enthusiast Website: Scirocco Terms

A1	All Sciroccos (1974-1992) were built on the A1 chassis. This chassis is shared with the Rabbit (Golf 1), Jetta 1, Pickup, and Cabriolet (1980 - 1993)
A2	This is used to designate chassis of the Golf (Golf 2), Jetta 2, and Corrado.
A3	This is used to designate the chassis of the Cabrio, Golf 3 and Jetta 3 (Vento).
A4	This is used to designate the chassis of the "New" Golf (Golf 4), "New" Jetta (Bora), and the New Beetle.
B1	75-79 Dasher
B2	80-87 Quantum / Santana
B3	88-94 Passat
B4	95-97 Passat
B5	98-current Passat
Mk1 (Scirocco)	Pronounced "Mark one", this is used to designate the early style Scirocco (1974-1981). Also known as "Scirocco 1" or "53".
Mk2 (Scirocco)	Pronounced "Mark two", this is used to designate the late style Scirocco (1982 - 1992). Also known as "Scirocco 2" or "53b".
Scirocco 1	See Mk1 (Scirocco)
Scirocco 2	See Mk2 (Scirocco)
53	See Mk1 (Scirocco)
53b	See Mk2 (Scirocco)