Engine decoding

The block casting numbers for all RB, B, and LA engines are found on the left (driver) side of the block. In addition, on 1968 and later engines the numbers stamped on the lower rail of the engines right (passenger) side match the last 8 digits of the cars vehicle identification number.

This is wrong for a couple of reasons.

IF a 1968 model year engine has a partial VIN, it will be on the back of the engine on top of the bell flange where the transmission meets it.

AND for about the first half or so of the 1969 model year, the FULL VIN was stamped on the lower pad.

And more about

2780930 340 1968-73 LA Except T/A & AAR

3577130TA 340 - 6 bbl 1970 LA T/A & AAR

- TA blocks have been found in 1970 cars in four barrel applications without the TA heads - in 1971 A and E bodies also & at least one in a 1972 model year car, a B-body.