Jack Gibbs was involved in a similar project. No Corvair roof but a stock bodied 69 Camaro. Can not remember the man's name. I have his name on my shop computer but have not plugged it in since I closed the shop. It was a real high end built......Jack built the engine and was kind enough to refer the owner to call me as I had a set of 65 exhaust manifolds they used on the build. Maybe Jack can fill in more detail and pictures.
I thought about dropping a 409 in one of my 68 Camaros but witout any body changes.
Could also drop a Corvair body on a 78-82? G body frame with 409 up front.