Hey brother, DO NOT, weld factory spindles. Not sure about Isuzu, but MOST factory spindles I have worked with, ARE cast iron.

You best be, would be to take the spindles to a fab shop..one thats trust worthy, adn have them make you some spindles.

Another thing, dont know if you have looked into this or not, is the ball joints. They only have a limited range of motion..so..I would recomend soem thing called Una-balls. I will try to send some pictures to you email(if you PM me with it). Cant promise when, but it should give you an idea.

HTH
Chase

And another thing, if I am not mistaken, he is talking about bracing from the upper and lower BJs, the TRE, and the spindle itself..though I could be wrong....