HELP: a/c accumulator opening measurement

[madcow75]

Looking for someone with a bare a/c cab. I am converting my cab from a non a/c cab to a/c so I need to cut a new hole for my evaporator opening/ heater core in my firewall. Can someone please measure the blower motor hole over to the evaporator firewall hole. What is the width and heigth of the hole. How far away from the cowl firewall body seam does the opening start at the top. Thanks the measurements would be greatly appreciated.