1970 M22 question

[1967Z28]

My friends and I got an M22 from an estate sale and had it all rebuilt. We were told it had come out of a 1970 Chevelle. There is an L in the partial VIN which indicates the LOS/Van Nuys plant. The partial VIN has some 7s in it that are a different font than the other numbers. Are there any 1970 Chevelle experts here that can fill me in as to whether this is an anomaly seen on other Chevelle (or Camaro) transmissions from the Van Nuys plant? Any help is appreciated. Thanks.