I am overhauling an Alfa 2000 engine, but everything was out of order. The engine was supposed to be a 2litre, so I got the parts for that version. Car is a 2000 GTV 1974. When i dismantled the engine, I found the head to be from a 1600. The block was from an alfetta, engine number 1068 = 1.8 1973-1976. So, I have a totally rebulit head with new valve guides and valves plus surfaced at the shop. The "old" 1600 head had a blown spark plug thread, beyound repair.
Very strange, the engine was running very good for three years, never opened. Funny how a 1600 head coops with the 1.8 block.
Now, I am putting an overhauled 1750 head on the block, so everything will match.
The
cam shafts were also new to me. Marked 10 03 2000 N for exhaust and 10 03 2000 P on intake plus the alfa logo. I don't know what they are, anybody who has a clue?
Always something new with the older Alfas.

Finallly, there are some Giulia shop manuals etc here
www.duettoinfo.com ROUNDTAIL SPIDER ORIGINAL FACTORY LITERATURE