SB Cam Thrust Plate questions

OK on a small block, I have seen them setup several ways with and without the oiler bolt. (this special bolt is thru-drilled for oil passage; its one of the four bolts that mount the thrust plate to the block; the other three bolts are standard bolts) I have also seen them with a angle tab steel plate in the hole too.


1st ?
Is the oiler bolt the one that goes in the left top passenger side corner?

2nd ?
Also my next question, on a 340 block there are 2 little hole below the larger drain holes in the galley of the block. These are on the side of the camshaft. Do these get the mini plugs put in them?


I know I have seen on racing engines there is also a kit to drill and sleve the lifter galleys with a tube etc..

3rd and last ?
Do I need that steel part or is the oil drilled bolet enough? Sen these on some without the oiler bolt mounted in the lower right.

thanks!