[Y-Blockhead]

Originally Posted by midgetracer

My guess is that the drive for the distributor /oil pump has came up a bit and the oil pump is not aligned with the drive. Try using the crank to turn over the engine slowly and maybe the drive will align and drop down into place.

The drive is held down with a reasonably strong spring, so I don't see that happening unless the spring broke.

At this point I think I would pull the manifolds and side cover and have a look see what is going on. You have been struggling with this for ~3 days now. JMO