You could try getting hold of a ‘So wird’s gemacht’, by HR Etzold, on the Mk2 Golf. This covers all Mk2 Golfs but is in German!!! You can always use the free translation software on the internet.
I’ve also noticed that the line drawings are very similar to those in the Haynes manual!
Alternatively you could get hold of the manufacturer’s workshop manual, if they exist.
Clive