upper a arm cross shaft

[jake72ss]

I have been trying to find a supplier that sells upper a arm cross shafts that have the provisions for caster slugs like the DSE a arms. I've found them that have a 6" bolt center, but not 6.5" for a chevelle. I have global west uppers now and I would like to change the ball joint sleeve to a screw in style and change out the cross shafts to the style I mentioned earlier. Any help would be great, Thanks,
Jake