4B297590, second # PP8334578
PP833 4578
PP = New Process
833 = trans type 4-speed
4578 = 10k assembly date code - Day 4578 is Friday, February 8, 1974
There should be 4 numbers after the 4578. That would be the build sequence number.
4B297590 is a partial VIN
4 = 1974
B = Hamtramck assembly plant
297590 = Sequential production number