They will be needle bearings.
Ok, so they don’t need to be pressure fed. IMO, one of the benefits of needle bearings over bushings in a lifter is they can live on splash oiling.
If I were doing it I would I’d skip the oil holes in the lifter bushing. There’s no need for it.
I would drill a new hole in the 2 and 4 cam bearings and clock the bearings so they don’t let oil get to the passage that runs from the cam bearing to the head.
Then use a set screw in the feed from the number one main bearing to the drivers side lifter gallery. That stops oil getting to those lifters.
I put the set screw under the main bearing. You can use a 5/8 cup plug in the drivers side lifter gallery and drive it in past the feed hole coming up from the main bearing.
Either one works but using the set screw stops a potential leak at the cam plate. It is such a minimal leak it won’t matter so either way to stop oil from getting up to the drivers side lifter gallery.
Drill into the vertical oil gallery that feeds the oil pressure gauge and tap it for 1/8 NPT.
Drill into the oil gallery that feeds the each head with 1/8 NPT.
Make up hoses like the pictures show.
Drill and tap the oil feed hole in the cylinder heads that feeds the rocker shaft. I think I use 1/4-20.
I start with an .060 hole in the 1/4-20 set screw if your rockers have needle bearings and .090ish if they are bushed or plain aluminum.
This will get maximum oil to the mains and eliminate the oil leaks at the lifters.
I also drill the galleries that feed the mains from the drivers side lifter gallery to 9/32. Some guys use 5/16 so if you want to go that big it’s ok.
That’s how I oil these. I minimize the leaks and I stop feeding the rockers from the oil that goes to the main bearings.
If you are not oiling the lifters or pushrod oiling there is no need for the crossover tube.
If you were going to pushrod oil or you wanted to feed the lifters or both you can use a 1/16 hole in the lifter bushing and feed the drivers side lifters off the same line feeding the drivers side rockers.
You still won’t be taking oil that should be going to the mains to feed the drivers side lifters, but you will be taking some oil from the mains to oil the passenger side lifters.
I use -4 lines. That’s plenty big enough.
