Hi Compare Vincenzo, Buon Anno!
You got good advice, but I would NOT open up the cam sprockets. Just put the cams back onto the chain to where they were. Make sure the cam bearings go back in right place. Oil the cams real well before tightening.
If you want to chat....519 542 7699 Elio
Hi Vince,
It would take me far less time to explain the assembly procedure over the phone than type it out. I'll send you a private message with my phone number.
Cheers,
Jim