The patch panel you need is the inner door bottom we carry them as do most vendors.
http://www.gmcpauls.com/Patch%20Panels.htm
In regards to the mention of drain holes for doors the original doors and repo's both have these drain holes on them, its just that most folks never clean the dirt & debris that gets inside the door out and it plugs the drain holes making them hold water. If you have good doors now be sure to open them and look underneath at outer edge of door skin and door bottom to see if drain holes are clear of debris.
GMCPaul