I don't remember if that architecture was being used when the switch was made in PS to let them use 5 speeds.

Of course, the Wayne County people stuck with idiotic low RPM and torque and kept the 4 speed while the rest of the class figured out 5 gears is quicker than 4 and then developed engine packages to take advantage of that RPM.

Again, IIRC what you are showing is in that time frame of WC taking a dump and the Dodge PS program had to retool and start over.

It's possible you have a short block that was for grunt and an intake that was for RPM.

Or, it's possible it's all be reworked and none of what's engraved on anything doesnt mean a thing.