If you're talking about the bracket on top of the frame just behind the steering box input shaft, that's part of the parking brake linkage. The slotted bracket in another picture is part of the radiator core support attachment, I believe.

Most all of the Saginaw Pitman arms have four wide splines in the tapered hole that slips over the steering gear output shaft, that's supposed to prevent the arm from being installed incorrectly. By using a 3-cornered file to split the wide splines, the arm can be installed on any spline, resulting in several optional positions to use while tinkering with the geometry of the linkage. I see someone has already figured out how to top-mount the steering box, which is much more practical than the usual dumb-looking method the commercial kit vendors use. You can fabricate steering stops for the spindles to prevent the tire from rubbing the steering linkage in a hard right turn. It just reduces the turning circle tightness a little.

Edit:
It's also possible to move the shock absorber mounting bracket to a position behind the axle to free up some extra space for the drag link when the steering gear is mounted ahead of the axle. You might want to move the steering gear far enough forward to be ahead of the core support if you don't want to alter that bracket- - - -just use a longer drag link.
Jerry


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