.......manual box.........

I think he's talking about changing an early (64-72) manual box to install MANUAL steering on a later (73-76) A body, so we are talking about "sector" size (the shaft that the Pitman arm slides onto is a different size on large sector.)

Info on big sector/large sector manual boxes continues to be vague and confusing (even on the big block dart site) but I believe we determined in our discussions here that only the POWER steering boxes used bigger sector sizes on the A bodies after 72. Depending on how you read the bbd site, supposedly only the trucks and vans got the big sector manual boxes, not the A body.

The last time I saw a post on this, the OP said the books alll listed the same Pitman arm for power and manual steering for 67-72 A bodies and then TWO DIFFERENT Pitman arms for 73 and up. One was for the 73-76 large sector power steering and one was for the manual steering with the small sector.

The person ordered the newer 73-76 MANUAL steering Pitman and it worked on the early box.

If all of this is wrong and the later manual boxes ARE big sector, you could still do the swap using ALL of the 71 Swinger parts including the drag link and the idler arm, basically converting the 76 Duster into the earlier pre 73 steering parts. They should work on the newer K frame if you use them all together.
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