RE drilling out the ECU ground lug...I can't remember. It seems to me that the OEM stud was 6mm and the one I went to was 8mm so if I did have to drill it out it wasn't a big deal. Remember, we are talking about copper.
One point I failed to make, these studs are doing double duty. On the male end they are securing the ground and on the female end they are the attachment point for the starter cover. It seems to me that every time you take the starter cover off you are inviting problems with the ground. If I'm wrong, it ain't the first time.
Growing old ain't for sissies!