If your worried about the sealing of the head gasket don't torque down all the head bolts until your ready to set the lash
As far as wiping any good brand cam lube off when setting the valves, DON'T
Assemble the motor, set the lash, seal it up and make sure and prime the motor just before starting it
I like to pull all the spark plugs out before priming the motor and use either the starter or a breaker bar to rotate the motor while priming it
Good luck