I used these energy bushing on my car that has an Art Morrison frame:
https://www.amazon.com/Energy-Suspen...RXD40KV0TCZ4Q7
I had the aFe Control PFADT Series bushing, but the c-clip retaining the bushing kept coming off, so the energy ones were the only economical option I found.
here's an article on a bunch of other options:
http://www.superchevy.com/how-to/cha...your-corvette/