I make headers all the time(thats part of what
I did at Chrysler)... these are 1 7/8" econo W-2
headers I made for my Rampage... I did the flanges
also... this is 3.5" collectors
EDIT
the flanges started out as 1 piece, that makes
it easier to set it up and for welding then I
cut them down to what you see.. they are also
3/8 thick so no worping