Questions for those that have done this. Pic below. I cut the hangars from a model A rear and am going to put them on the '40 rear What spring did you use? Custom or model T or ??? As it stands now, eye to eye the mounts are 49.5 inches apart. I have a T spring that is 45 inches eye to eye. The shackles are 1.5 inches eye to eye each. Install the shackles and I am left with about 1.5 inches of gap. Does that seem about right? I am also debating whether to bolt them or weld them or both. I lean toward both, but doing the welding delicately so I don't melt the seal in the diff.
You can use either, depends if you want to lower it with the T spring. I would weld them where your gap is around the ears and the bolt them. Also on my rear the hangers kicked the spring to the rear some so I had to re-adjust the angles. http://www.jalopyjournal.com/forum/threads/automotive-a-d-d-the-28-tudor.753531/#post-10453080
I am going to have to use the T spring I think. I don't think I can stretch an A spring the roughly 3 inches I would need to.
You know the stock "A" perch eye spacing was 49-1/2" center-to-center; while the "T" perch eyes were on 48" centers. 3" is not a lot to spread the spring. I would use regular hex head bolts to attach the perches, don't think the thin square head bolts would be good for the tension load of the perches as compared to the shear load of the original application.
You can also take the spring apart, install the main leaf by hand, and reassemble the spring in place. Easier this way on a spring-over as the banjo gets in the way of a regular spring spreader. Just be sure to use quality C-clamps and let them do the work, only use the all-thread to keep the leaves aligned.
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