1971 360 harmonic balancer question?

............., they r certainally different looking........71-77 has a big ellipictical weight on the front of it where the pulley mounts..............78 up the weight is taken out from the inside [back] of the damper.........i cant say 4 sure if they r weighted differently, but i think not, as mopar only list the converter balancing weights as LA or magnum.......kim.........