dude will you be my best friend you build the coolest stuff for no money...How do you do it? I'm just gonna drop my truck off and give you like 3000.00 and say trick her out....Your stuff is bullet proof. Dibs if you sale the yota you just built. This would be a fun urecross truck.
I'll say the stock welded arms are good enough for street use for two reason, well gussetted and cast or forged steel aloy. Not cast iron or a similar high carbon deposited type metal with large grain size. The arms simply wouldn't take the stresses in stock form made out of anything else. Having said that its still not something a beginner or a small welder should be constructing. The material is vary similar to a high tensile strenght hook for equipment, lots of those get fabricated and welded to this and that for all types of reasons. I haven't ever seen one of his break, mater-a-fact I think he bent one where no welding or cutting had been done and the rest stayed put.