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Leaf spring mount distances and shackle lengths...

Going by look isn't a bad route with fairly flat springs. The more arch and travel they have the more critical shackle hanger placement is imo.
Those front leaf springs are from my old '99.5 F-350 PS.
They had less than 5,000 miles on them when I upgraded to a 4" lift.

The reason why I used them on my Bronco:
Poor/I already had them.
The center pin moved the axle rearward 5"
I wanted flatter springs.
They're 1ton springs.
This front hanger is just hanging by leaf tension from the spring resting on the floor.

I have my rough location marked but due to how I welded my frame main eye hangers… I’m slightly outboard.

I could cheat this on the front and weld the hangers on the front bumper/cross and they will remain supported and I’ll have a better approach angle. I can’t do this on the back due to how the Willys rear body mounts are set up.

Option two, I cut the frame side mounts I tacked on and center the fixed mounts. I wanted them flush on the inside so the mount and the frame overlap could be tied in with one huge fish plate.



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Bumping this. Is there a formula to calculate how far back the axle will move on compression for a given arch/shackle length/angle?
axle movement itself is relative to the fixed eye and the center pin, not the eye to eye.

A (along leaf surface) - A straight line = how much the center pin will move when the spring is flat.