Somebody upgraded those springs.Typically the bands would keep them together.
With soo many leafs,the center pin will not keep them together.
The mains are probably toast.
In your pic on the firt page you can see that the righ spring was rubbiong the frame rail just behind the front eyelet.
I used the Mopar Repop B body rear spring shackle kit that included bushings.
They are identical to the 65-68 C body rear shcakles and bushings.
Front bushings are readily available from yur local spring shop,or on E bay.
For brand new springs,I highly recommend Alcan.
They can build a set of springs to your specifications for a reasonable price..
I have C body buddies use them,and I drove their cars.The product they deliver is awesome.
http://www.alcanspring.com/