[Bob Bidonde]

In addition to the excellent info by James Rogers, you have a 3.5 degree angle on the engine as it sits in the frame.

I have had more than one case where a wad or partial wad was left in the rear main bearing oil drain passage. The purpose of the wad is to keep new babbitt from flowing into the oil drain when it is poured. Remove the plug pressed into the rear main cap to check that oil drain passage is clear.