Have you look at the AR engineering plates that AndyF on here makes and sells? If not maybe you should see if they will work for you I've used one to install a 426 Blown gas street Hemi motor in a 1971 Cuda so I could locate the motor to clear both valve covers.
Yeah I looked at them and seen them, I don't like the look. I figured somebody should be making one that looks like a one-piece elephant ears. There was somebody that custom made them online here.