G28T center cam bearing oiling?

[OHV DeLuxe]

I now have my rebuilt G28T block and bottom end on the bench, and as always i go through the oil passage system.
These are as some of you know full pressure B type block, they have a solid top oil pump like commonly used on modified regular A and B blocks.
so my question is how does the center cam bearing get lubrication when the oil pump is sealed of on top and the only hole into the cam bore is where the drive meets the cam, this is above that sealed of level.

Thanks.