Been there, done that. I put a Hemi in a Dart. I don't know if this will help you, but what I did was to go ahead and move the top shock mount over about 3/4" and remake the fender well area near the valve cover so that I could pull the valve cover. In the end, that was the best solution for me.

And it is so tight in that area that you really couldn't tell that the work had been done.

In my 70 Cuda, I wanted to use stock 70 style stock Hemi covers, so I modified them to clear the exhaust rockers. And with the wrinkle paint, you really don't notice the dimples.