I'm doing a dry run putting the Shaker together and I'm finding that the cold and warm air doors are binding a little. Neither door is closing all the way when I use the short cable. Is it better to shave a little out of the inside of the bubble, or can I get away with adding a couple of washers between the door mechanisms and the bubble itself? The hot/cold air door connector bar seems to bind a little as well, but it might be because of the doors binding so I'm planning on tackling one issue at a time.