Joe - who're "they"??
as Tim points out, the shop manual shows a straight axle [57 manual has the same pics] - it also points out that IF it's bent, great care must be taken to straighten it [cold - no heat on castings], and beyond a certain amount it should be replaced, and it's unlikely many of these ol trucks have had any front end adjustment done by bending the axle front to back - it's up and down that would be bent to change the kingpin inclination, and that's unlikely - everything else has specific adjustment points, and I've never seen a manual that advises any bending operation for alignment
Bill
