@ By-Tor
Thanks. There is nothing wrong with forgeries in my opinion. The last Rolex AD service cost a $1000 (Australian). For that I got a new crystal, bezel insert, hands and a service. They also brushed and polished the case.
Unfortunately they didn't return the hands which had a nice patina to them but apparently this is standard practice but I wish they had left the old hands on.
The watch has an interesting history. It was purchased by my dad while we were on holidays in Italy in 1973 (however its a 1970 build, apparently it had been sitting in the window for 3 yrs), I was five at the time and still remember him pointing to it in the window and haggling for a better price. Anyway he gave it to me for my 21st birthday present. I'm planning on doing the same.
Anyway enjoy your 1680.