well dude its pretty simple,,,of course all welds have a bevel,,but the edge isnt featherd,,you gotta put a landing on it. just take that grinder(i use a 9 inch) and put a blunt face and the end of the bevel about the thickness of a dime or a nickel that way you dont blow the walls completely down and undercut it when you jam your bead in it. first off make sure both bevel landings line up good,,,the hi -low's good mainly on the inside,,fittings and stuff are bad for hi low on the OD but generally jam up good on the ID. leave about a 1/16 to 8th inch gap on the top and just tack it. your gonna have a high point on start where you didnt tie in, forget it,,,tack the bottom and make sure your gap is the same all the way around( this is just for practice of course,,,good all the way around may not be in the bubble if you know what i mean). once youve got it tacked up,,,take your grinder and grind only the starts,,,the parts that didnt tie in,,feather em down until there about flush with your landing that you put on before you fit it up. or until they turn blue,,,basically grind it so you can get a bead in it. take off on the center of your tack and just push that rod until it goes through,,,youll know when it does,,,and be sure that rod doesnt burn to one side,,,you may have to work it a little but make sure you tie in on both sides and just run it down hill. when you brother n law man,,,one man fires off on the top tack and takes off then the other about the same time. you should have about a 2 inch tack to get started and your gonna grind it anyway. when you weld the rest out one man will fire off and itll be hot enough that the other guy will fire off shortly there after and youll be able to tie in good and clean. you got any more questions just let me know.