I saw a pair of studebaker center bolt valve cover on a late 80's chevy 350. I think they were off a late 50's studebaker 259 motor but im unsure of that. They looked like a direct bolt on, but I only saw a picture of it in hot rod a few years back. Youd be able to keep your motor if it works and just swap the heads and the valve covers and 95% of the public would be fooled.