If this is an automotive application (i.e highly automated), I would look at low current Plasma Arc Welding. You get all the same advantages of GTAW (TIG or Heliarc as some say), but you get better arc starting. In some GTAW applications at low current you can blow away base metal when the arc transfers. PAW equipment is just slightly more expensive than GTAW and automation is often less difficult.
William Roth, PE, CWI