I just got a deal on a chevy rear axle, drive shaft, and 350 trans. But I noticed something I had never seen before on a 350 trans. On the bellhousing on the left top side is a large 7R cast into the housing. Its actually a raised number and letter. They are about 7 inches long. What does this indicate about this particular 350 transmission? It supposedly came out of a 70's Camaro.