I am new to the foum and i got my hands on a 500 gal propane tank all ready mounted on a trailer. I am need your advise what to do and not to do. I have been told to fill it up with soapy water before cutting into it so it pushes the rest of the propane out. So 1. What do i do before i start to cut into it? 2. Pros / cons reverse flow? 3. Pros / cons direct flow ? 4. what do yall recommended for that size tank i mainly going to be doing ribs chicken Boston butts and occasional hog. 5. what size fire box and size stacks and how many stacks 1,2 or 3. thanks again for all ur help looking forward to learning lots!!