Dumbutt Question.....

I haven't looked inside a sl/6 for like 25 yrs or more, but I do remember that the oil pump bolts into the side of the block, midway along the block down low on the Rt side. It's driven off the gear teeth cut into the middle of the cam, and the oil pump mounting face has ports cast into it to mate with ports on the side of the block. Now on the earlier, pre-1980(?) mechanical lifter slants, there may not be a lifter oiling gallery. It might just be splash/drip lubrication.
For the hydraulic lifter slants, they must have an oil gallery, but I can't say I've ever seen one taken apart, so I can't say what it looks like, or specifically where to look.