Barn fresh find today, can you help me?

I have a 340 with the same type of numbers, OR247269.

There's no way to tell what it's from. Numbers from the front of the block, just under the drivers side head, will reveal the day the motor was built up. It should read something like this, here is mine:

FWP31390007

F = 1970
W = Windsor
P = Premium Fuel
3139 = Mar. 2, 1970
0007 = seventh motor of the day