Having trouble getting 0 to positive caster as required by the new Borgeson steering box. Is the lower a arm where it attaches to the frame adjustable? When I was changing the lower bushings I noticed one end was slotted.

Been a while, used to login as Capt Ken

 

Welcome back. Most all of the adjustments are made off the top A arm. If you need more I think it's possible to oval the bottom mounting holes to gain a few degrees.