I ended up having a friend stretch and re form and re weld the rubbing area inside the valve covers.
Now the Valve spring edge on top inside the valve cover edges clear from rubbing.
Clearances inside the 426 Hemi valve covers are dangerously close.
The issue is:
If you put a bigger cam in a Hemi; chances are the valve springs will be a bigger diameter than what OEM one's were since they're a higher rate spring load.
Most machinists have no idea to the fact that 426 Hemi's have very tight clearance inside the OEM valve covers.
Also...Valve spring height needs to be specifically addressed to the head machinist to avoid any issues.
That also can be the culprit.
That means you must use a thick gasket.
And/Or: an after market valve covers.
And/Or: modify your OEM's by stretching out where they tend to rub.
OEM valve covers can be modified using heat and dolly the rub area out.
0'ing out the valve cover bolt holes to shift valve cover down is not a good idea.