the newer engines have a deflector....., and it goes in the oil galley hole. (plugs it off)
I went out and looked at a engine I have ready to take apart, it has a plastic cam gear, so I am sure it is where it came from the factory. And the hole is at the top left. On the deflector, the oil running from the valley runs down the block face, and onto the deflector, dripping on the chain before it hits th ecrank gear. On the oil hole, it is at the low part of the valley, and oil drips out of the hole, and onto the chain, almost in the same spot.
I dont think th echain oil is pressurized, since it dont take much oil to oil the chain. (the windage does a fine job, except at idle)
im looking thrue a couple books right now, maybe ill find something..............
nothing yet.......also, the main oil feed to the crnak is in th egalley that your tapping into, might not want to waste any...............
AHA! A very old book sais..............If one of the four bolts for this plate has a hole drilled through it, this bolt goes in the passenger side bolt hole-top left looking at front of the block. Remember, this bolt allows oil to drain from the valley onto the timing chain. Some engines use a small drip pan rather that the hollow bolt.