Model A Ford front caster
 

I have been told that the frame on Model A's establishes the front 5 degree caster angle and the front radius rod when mounted on the bottom of the bell housing reinforces the setting. Judging by the number of front end collisions a Model A might have in its life and the fact that the front axle is symmetrical and does not establish the caster angle unless further bending of the king pin bores section of axle between it and the spring perch holes is bent back. How would one suggest checking a frame for the 5 degree bend back?

Re: Model A Ford front caster
 

I check my king pin caster with a protractor. I use a sliding T bevel to measure the angle of the king pin caster against a level floor. I then measure the set angle found on the sliding T bevel against my protractor. I have hand built front axles for our antique cars and I have tried different caster angles. For easy steering and having the wheels easily returning to the front after a corner, 5 degrees is a good caster angle. The 1911 Stanley pictured I scratch built starting with just the engine. In setting the caster angle, set the sliding T bevel to 5 degrees and then bend the Model A axle to match.