KZ 750 R from 1982 - mixture screws basic setting

I disassembled and cleaned the jets of the Mikuni carbs on my KZ 750 E (KZ750R018xxx).
Now what is the basic setting for the idle mixture screws - how many turns from closed?

I have a service manual but it fails to mention the setting; maybe the screws were sealed originally and not meant to be changed.

2.5 turns from lightly seated is a good starting point. Once the bike is up and running, warmed up, a vacuum sync should be done and you can tune each screw a little until the highest idle speed is achieved. All should be within 1/2 turn of one another. A large fan should be set in front of the engine to keep it cool while syncing and performing tuning if the job takes more than 10 mins or so (which it typically does.)

Fine, thanks!