Iron Ductile Questions?

[68CoronetRT]

Ok. Got a new one for you guys.

Just purchased a full set of the Crane Iron Ductile rocker arms(Used) and I have 3 questions.

1.) I plan on putting them on stock shafts. Do they just slid right on? (No bushing needed etc..)

2.) What am I supposed to use for spacing? I have hardened 'spacers' but do not have any of those mini springs.

3.) Geometry wise, 1-3 threads showing above the lock nut after the lock nut is tight correct?

Using these for my hydraulic cam and figured out each full turn is .040, so my plan is to set to zero lash and then turn them 3/4 of a turn(preload) and thats it!