Yeah, you really need to fully disassemble it and bolt mod it. You can get new springs from Unicomp to replace the gross ones, or you can try to clean them, but they might be beyond saving.
Bolt modding is pretty easy, especially if you follow jpc's guide. That's where I learned to do it, and I've done several dozen all told now. Just be patient, pay attention to the details, and make sure everything is dry before you put it all back together.