i couldn't trace the block code you listed. where did you get it from? check the right bank in front of where the head bolts on. you may need to have a small wire brush to read it right. A visual inspection however an LT1 has 4 valve cover bolts that go down thru the center of the valve cover rather than on the edge. Even then then are 2 or 3 different versions that i know of one being an LT4 out of corvettes. You can save a lot of time by running your block numbers at
www.mortec.com. they list just about every chevy V8 casting number there, they tell you displacement and date of manufacture also