(1) Remove the set screws and lock them in a drawer. You do not want to restrict the flow of oil to the heads.
(2) If you have the shafts with the 2 sets of holes. Put the rockers on the head with the spacers. No pushrods. Remove the adjuster screw. If you have already plugged hole on the push rod side. Then bend a wire and isert it in thru the adjuster hole to the shaft. Now rock the rocker arm back on the shaft and see if the wire doesn't go into the hole in the shaft. Mine do. your should too.
(3) Stay with the .100
(4) Where did 4 go?
(5) You are using a modified hydralic lifter with a curved face on a flat tappet cam. You will destroy everything you are working for. Put a hydraulic cam in place of the solid cam and the lifters will work.
(6) 1 thread is what is recommended
(7) you are lucky LOL
I want too see your oil pump and pickup