Help with Quadrajet Identification?

[Cadillac Kid]

Hello everyone,

My friend recently picked up a 1973 C20 longbed with the 454. The truck is pretty orginal and we are currently cleaning it up and attending to the years of neglect.

I have a feeling the quadrajet on it may not be the original one. I have looked at the number decoders before but this paticular one has me confused. The chart I was looking at made me belive it was a 1975-1979, but with further decoding it was telling me it was a 1984, maybe it was a bad chart, or it was me haha. If you could help decode this carb that would be a big help. The carb number is: 17054919

Thanks!