here's a pic or two of the lower bolt mentioned earlier that must be removed...mine were rusted pretty solid hence the hole in the door and the screwdriver as a brace in the second photo...the bolt is a 5/16 x 18 that requires a 1/2 wrench

http://i1206.photobucket.com/albums/bb460/gibsonflatpicker/ventlowerbolt_zpsf286566e.jpg

http://i1206.photobucket.com/albums/bb460/gibsonflatpicker/ventlowerbolt1_zps16420efd.jpg