I an new to the site and have a case of Smokin Feaver. I have low vision and use a screen reader on the computer. It will not read the format of the Reverse Flow Calculator . Can someone help me to find the answers to these questions? 1- the cooking chamber size is 22D x 48W . What size round fire box is needed? 2- What size should the fire box opening be in the cooking chamber? 3-What size gap is needed at the end of the baffle plate be? 4 What size and heith should the stack be? 5- I know this maybe a dub one. Is the drain left open while cookin of is it just cleaned after a cook? I want to thank each of you in advance for your help.