welp , if it was me i would make a template of the extended pattern, make it like the adapters you already have made,use a angle grinder and a vise and shape it in, when
ya got it then take it to a local welding house or a friend that has a Tig or Mig welder,
i'm thinkin those bars are made from chrome molly tubing or cold roll steel. also if ya extend it, the area ya weld isn't rewelded cause it was never connected in the place of the weld before. chamfer the edges of the butt weld and have em fill it in , grind it smooth and rechrome... two lane is right about the extended length, but i think it will have a factory finish appearance and nearly the same strength, you could even prime the extended base braket and paint it and save the chrome cost [smiley=laugh.gif]