FWIW and a bit off topic..........I am converting my H2B to the 3 line 72/73 oiling system........I think the H2B\C 3 into 1 line is kind of screwball and starves the far cylinder to some degree........and have discussed this with someone a bit more knowledgable than myself
I modified my 74 cylinders and added the 3 oil jets "VM 22/210 30" pilot jets, cut of the tube with a fine saw and filed them up, found out the drill size for a 5mmX.08 tap.........only drill part way (don't come thru the cylinder port)......tapped the holes (it was a tapered tap) so it only part way threaded the hole's which is fine........put a touch of red locktight on them........they screwed in nice and tight until flush with the cylinder base.......easy

.........and I am using 73 cases so I don't need to drill the cases
THX Phil