Wow, just to see what would happen I called Edelbrock tech last night and described these issues to the tech as if they were mine.
The tech told that I must have got a pair of heads prior to the ones where they began adding an angled pushrod hole to improve the clearance problem. Which I thought was huge to have someone in this day and age actually admit that I could actually be having a problem with a product. Tech went on to offer that I could send my heads in and that they could have punched those holes for me on their machine, exchanged my valley cover plate and helped me out as much as they could.
Problems suck, and literally suck the fun out of projects. Sorry, to hear that you had so many problems, but when in doubt call the guy who made the part first and maybe you could have saved lots of time and $$. My dad once told me that I'm not being fair if I get mad at someone without first giving them a chance to fix the problem.