I reread you post about new kingpins so I edited my "check your kingpins" (Duh?! smile )
Are there any caster shims present?
I have the same style power steering in my '49 3100 and needed to increase the caster shims to 5 degrees to get the truck to handle properly.
When you come out of a turn, it is the caster which brings the wheels back toward straight ahead when you let go of the steering wheel. If yours does not do that, you need more caster. 5-7 degrees is what many end up with to fix this problem.
Replacing the heavy inline 6 with a lighter V-8 may well be the cause for the need to increase the caster angle to restore proper handling.

Last edited by 52Carl; 09/30/2021 1:02 AM.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission