wheres my oil preasure going

There is an oil galley plug in the rear near the distributor,
that was left out, by the machine shop,
when I was rebuilding a 340 years ago.

The oil pressure was low, even with a high volume pump.

I made sure it was installed by ME, when I rebuilt the 318
i have in my Valiant.

Inside the threaded plug,in the left of the picture;
is another internal galley plug.