You want to go with the closed knuckle with disc? I am opposite, I would rather have an open knuckle with drums. Oh, wait; I did have that. 1970 axles were drum with an open knuckle... a one year axle... don't buy one!
If I were you I would go with a later axle and be happy. Disc with a closed knucke? The only person that's going to know it's a closed knuckle is you. And a few gear heads. These are large production number vehicles anyway.
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