Hi
The GTL Scirocco mod is built to the late 70s division 2 ETCC rules, so it is for sure an ETCC car.
Division 2 rules:
1300-1600cc cars.
Min weight 775kg or 1708 pounds (GTL showroom weight is shown with a driver of 80KG so 855KG or 1884 pounds)
Max tire with 10.5inch
1600cc engine (GTL power 188hp)
The Opel Kadett in the Game is a faster Division 3 car 2000 to 3000cc class.
There was at least one Division 2 Opel but there is not one for GTL yet.
The Escort that is in GTL is basically an early Group 2 car before the big rule’s changes of 76.
These cars were allowed a lot of freedom in terms of modifications and were also not direct competition for the Scirocco.
There were 1600cc MK2 Escorts that raced in Div2 but again none in GTL yet.
The main competition for the Scirocco in Div2 was this car.
http://www.racingsportscars.com/etcc/1977/Brno-
1977-06-05-055.jpg
The Scirocco will be I think the First Division 2 car that will be in the GTC-76 class.
There is also the Trans Am version of the car that was also built to division 2 rules
And the late 70s early 80s SCCA GT-3 car.
Which had a dry sump super vee version of the 1600cc engine but was a also a bit heavier