If you are indeed discussing caster...
Model A wishbones where they connect to the axle are fairly close to zero. With the unsplit bones, the radius rods attached to the bottom of the transmission and traveled up to the front axle, giving it about 6 degrees of caster.
On a 32-34, the front end was lowered to give the car a sleeker look, so you will find that those wishbones openings where the axle connects are canted or tilted back, or up toward the sky. They built in the caster on the 32-36.
If you are splitting Model A bones (already close to zero caster laying flat on the ground) and then mounting the ends to the frame (higher than the bottom of the transmission) you are now tilting the ends down to the ground, and hence your negative caster.
The old trick was to piecut the ends, tip the openings back to the caster you need and weld 'em up, to be more like 32-34 bones.
You can't put 32-34 bones on a Model A axle. The spring perch opening on a Model A wishbone for the Model A axle is 2 1/4". The 32-34 wishbone spring perch opening is 2"
1928-1931 spring perch opening - 2 1/4" and maybe 1-2 degrees caster laying flat on ground
1932-34 spring perch opening - 2" and tilted back more for more caster.
1935-1936 - still 2" opening, but now have spring hanger built in.
1937-1941 - opening enlarged back to 2 1/4" (would fit model A axle) They also have the spring hangers built in, but this one has been cut off.
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