front end setup?

[texastrendz]

this one here is for the front end guys. how much positive caster is needed in a truck front end setup? i had ekstensive metal works build me a set of tubular arms for my dually project. the arms look great, but where they welded the arm mounts seems like it is going to give the truck negative caster. i have heard this is bad to have. i.e. shopping cart wheels have positive caster. any help would be great. once again thanks guys, and gals.
the truck is a 3500 crew cab dually, it is a 2000 but is the old body style.