To find the year of the block, look on the block just above the starter. You'll find a number cast into the block. That will give you the year of the block.
In a SBF, any small
oil leak will show up on the block plate. They all look like a pan gasket or rear main seal leak. One of the mechanics I know has a smoke machine designed to find the leak. He plugs it into a hole in the valve cover, and injects a petroleum based smoke into the crank case. Whereever you see the smoke come out is where the leak is.
I had a leak that I thought was a pan gasket. Turned out to be the fuel pump block off plate.
Whatever your local mechanic charges you to do this test is well worth it.