Not sure on the Giulia w/w motor but a 68 1750 GTV motor, also with a two speed, three wire motor, is wired thus;
Red - unswitched hot (park circuit)
Green - high speed
Green AND white - low speed
There may also be some usable information
in this post.
If you'd like the color Giulia Super wiring diagram (has no wiper terminal numbers) and/or the 1750 Euro GTV diagram (with terminal numbers), please send me your email address in a private message.