Rear spring question /Model A

Im setting up the rear spring,and made the mount brackets that mount the rear end to the spring.
I havent welded em on housing yet,

I am using speedy bills shackle kit,and it will have the'T" shaped affair that is on the opposite end of the shackle- to bolt to this bracket I made .My question is this:
It said in speedways description that the spring was for 42-1/2" mount spacing....I am****uming that is the distance between the left and right spring eyes-LOADED??????
Now- how far apart should my two brackets be spaced>
do I spread the spring with a spreader till the two eyes are that spacing or what is a normal amount of distance between the two [vertical]-rear facing brackets that are welded to bottom of rear axle????
anyone help me here? THANKS in advance

 

i'm not sure about the parts you are using , but on a stock model a spring the hanger brackets on the rear end were 48" center to center. a stock model A spring had 38-40" center to center eyes unloaded,depending on how many leafs it had.

the shackles add 1-3/4" per side , then the spring had to be stretched on to the hanger brackets. you will end up with the shackels at about 45 degree then


42-1/2 sounds short..is this a model a spring? what is the unloaded length of the spring? what is the speedway part numbar?