Depends on how much you want to spend and how nice you want it to look. I bought a header kit from Jegs and a few extra j bends from summit. You can also buy weld rings so the welds don't protude into the tube when you butt weld. When i decided I needed two tube around the frame I bought cheap slip on collectors from summit. I used steel tubes and mig welded them. Looks like crap on the outside, looks fine on the inside.

https://board.moparts.org/ubbthreads/show...rue#Post7358657