considering you said you are a rookie welder, i would first buy some scrap metal of dissimilar thicknesses to practice on after that if you feel comfortable enough go for it. i personally think it needs to be tig welded and made of stainless but thats me.obviously you are going to be dumping some money in this build dont skimp in a high heat high stress area. you also dont want to keep buying flanges and tubing because of burn through. good luck and lets see some pics