Edelbrock heads question
I think mine were stamped,not sure.
Apparently the castings are the same(607
69), the difference being the springs.
The 607
79 head is listed for flat tappet cams and uses #5767 springs, while
the 607
75 head is for roller cams, and comes with#5845 springs.
The seat and nose pressures are significantly different.There are links at the bottom of the page. I was unable to find anything pertaining to the milling of the tunnels for the roller heads, but I bet you the roller heads have it.
In any case, you own these now, so I think you are gonna have to clearance the tunnels to move ahead.
Aluminum Cylinder Heads - Chrysler - Small-Block - Performer RPM - Edelbrock, LLC.