@madmike1157 , I am balls deep in this 4R70W swap since my C6 decided to start slipping horribly out of no where. After cramming the huge b itch up in there, I find out I cannot reuse the C6 engine plate (wishful thinking, considering they share the same bellhousing bolt pattern). My question is this. The starter bolt holes do not match between the C6 engine plate, and the 4R70W bellhousing. That makes me assume my starter will no longer bolt up and work on the current flex plate? Of course it is zero degrees out (about 40 in the garage with my propane heater), so I am trying to research whether I should continue this venture, or throw in the towel and put in a T5 and try to sell off this big heavy assed auto. I cant seem to find where any other flex plate sizes are available, so if the current one doesnt work, I have no idea where to go from here.