Funny when one guy gets your handle wrong everyone thereafter gets it wrong. Renzo, before spending a bunch of $ on tires make sure all the mechanical components are in tip top shape. Be sure to follow the service manual instructions for adjusting the steering box. If it won’t adjust then a rebuild is in order. Once everything is tight and within factory tolerances if it still wanders when driven, try the radials. Welcome to the Stovebolt madness.