If it were me, I would be sending those puppy's back quicker than flies on poop.
Seriously, you will most likely end-up with a nasty, never ending exhaust leak which isn't good. I've welded twice in my life and I think I could do a better job than that!
Good luck,
E
PS - I have BBK equal-lenght headers and the welds are very nice - kind of like the driver's side of yours.