Model A rear spring mounting

Hi

This new to me so I need to ask for some information. I have a 56 F100 that I know every nut and bolt on that truck but I don't have very much knowledge about a 20's car/truck. At 69 yrs old I guess it's time to learn.

I bought a pile of parts at the local swap meet that when finished will be a 29 Model A roadster pickup. I have a 57/59 Ford 9 inch and would like to use it on this project but I need to know how far apart do I need to space the mounting brackets to use a Model A rear spring.

Sure seems like a lot of ( I's)

Thanks Chuck

 

On my model A sedan the shakels connect to brackets on the backing plates center to center as close as I can tell 49 1/2"

 

Thanks