340 engine help

Ok so I went to look at a 340 motor today that has been sitting in the back of this womans garage for what she says about 10 years now. It is not in a very easy place to see so I did my best to get the casting numbers on the drivers side and the other numbers on the passenger side down by the oil pan. I tried to get the numbers from the drivers side just below the head but I could not see a thing so those numbers I do not have. The casting numbers on the block on the drivers side read 2760930-340-4 the only number that I was not sure of was the 3rd didget it might have been a 3 if so then it was 2730930-340-4 and the passenger side numbers read 1B203129 which in some of the other threads that I have read means 1971, hamtramck, and the last 6 numbers of the vin from what ever car this motor came out of. Can anyone tell me what the casting numbers mean from the drivers side and anything else you might know about these numbers.
Thanks
Bob