I am shipping the pipes with one of the lower sections tack welded only, so that it can shortened or lengthened easier, if need be. If it fits good out of the box, you can just have the seem welded up when you get the flanges. But it is important that it stay 'clocked' as it is, because this has a big effect on the placement of the upper part of the pipe. Also, the upper section, due to the v-band, can be clocked as well, so that it can be better fit to various turbo setups. But again, the lower section, because of the v-band being on a 22 1/2 degree section of pipe, needs to stay clocked to the lower 90 degree section as it is shipped. I will include an instruction sheet.