Front Bushing ID for A-body rear spring???

That's what I have. MP SS springs. And they have the 5/8" sleeve for the bolt.

Thanks for answering my question.

If I order another set, they will have the same diameter bushing ID. So I will have to drill out the holes in the spring hanger and get some 5/8" bolts and nuts from a local hardware store...

Yup, you got it!