Building custom headers - advice

[79 Camaro]

I built a 1 7/8" set for 67 Nova LS swap this winter. Used mild steel. Never have built a set before. Took me about three weekends. Turned out good. I would do it again. Lots of cutting fitting and grinding to get the gaps close before welding. Not tough just time consuming. I went with 16 gauge tubing. It's a little thicker and easier to weld for me.