What is the correct/preferred method when installing studs. Does it make a difference which studs are used (head/mains/exhaust/rocker shaft...)?

I came across the following methods and there is no clear answer (even ARP gave me two different answers):

install block end of stud dry
install block end of stud with engine oil
install block end of stud with moly lube
bottom out stud finger tight
bottom out stud hand tight
bottom out stud and torque down (double nut)
drop a bearing ball in hole before inserting stud
use moly lube on top threads and between washer and nut
use moly lube only between washer and nut
use moly lube on top threads and both sides of washer

which method do you prefer?

The lubrication in the block end does not matter. A little oil or moly is a good idea.

On the other end, moly on threads and both sides of the washer.

I was taught to bottom the stud and then unscrew around half a turn.

studs are the way to go anywhere you can use them. BUT, beware most studs manufactured only have 1/2" thread engagement. That is not enough for aluminum heads or block. You also don't want to torque studs into the bottom of threads. You want the stud to bottom in the hole. Ideal situation; bottom tap all threads, turn 2 or 3 threads off stud and put drill angle on stud bottom. Then torque stud. Then you can torque it dry or with lube, doesn't matter.
the 1/2" thd engagement I refer to is usually on 5/16, 3/8, and 7/16 studs

I put a small amount of lube on the coarse threads just to keep the stud from seizing and then run it it finger tight. Use some ARP lube on the fine threads and torque it together. Doesn't need to be more complicated than that.

Actually in fastener training I was taught that on a bolt the thread friction and under the head friction was fairly close and if you have lubricated torque values you must lubricate under the head (and/or washer) as well as the threads. Same concept for studs.

I usually add some thin oil to the threads before inserting. I have found that some might stop before bottoming using your fingers. I use a allen wrench to make sure they bottom out then back turn 1/2 turn. Add ARP assembly lube to upper threads,washer and nut surface. Note: dry, oil, and different assembly lubes will change torque specs. Read up on what process you will be using .