6 Lug disc brake using 88-98 spindles ?????

[-T-]

So i researched the tech articles and thought that I had followed them to a T, however I took the truck to get aligned today and with no shims in the top, its still 1.3 out. I used 73 C20 lower arms, stock uppers arms, 88 upper and lower ball joints and tie rod ends. Everything went together great, but you could see that the caster was way off when it went together but I thought that it would align out. Wrong. Any suggestions on what I did wrong?

Has anyone else ran into this? any help would be great, thanks