I think you may have over corrected your caster with those Delta 4" arms. In which case a DC shaft is how most folks solve this.
You *should* need about 2.5 degrees of caster correction with a 2-3" lift and that gets your drive shaft angles where they should be.
For curiosity's sake... what height lift are you running? (measurements from hub to fender are helpful, as long as you aren't trimmed). What type of caster correction did you install on the front axle? Do you have your final caster numbers?
I've been doing a bit of reading and it seems that...