Opinions on rear spring idea

:read2:My 73 4dr has the typical A-body drop-*** syndrome I'm thinking about taking the springs to a local spring shop to have them re-arched and I was going to put one new leaf in each one to help. I'm just wondering if anybody has tried this, I'm thinking that the new extra leaf in each side will help to maintain the arch. I'd like to buy all new springs but unfortunately I'm on a pretty tight budget but still need to get the back end up a little. Any suggestions or ideas would be appreciated. Thanks