Please critique my home front-end alignment method

You could pin the metal Yer using fer the tires to turn on and take Inkzall "Milwaukee tools" and draw out ° "degrees' with a Speed Square....

Make yourself a pair of slip plates with some old tile or something..put some grease in- between... then the suggested speed square or such and mark out center and then + / - 20° I used that and string (front to rear...and. plumb bob vertical)

Good luck

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That's a good idea for laying out the degrees. What I don't understand is what is magic about 20 degrees? If I am turning the tires the same amount both directions by using the steering stops, aren't I basically doing the same thing? Again, I don't really care what my caster numbers are as it looks like 3 - 4 degrees is best-case you'll ever get with factory uppers and offset bushings. I just want to know if what I am doing is a valid comparison of the caster value on each side, whatever the number might be. Isn't caster just found mathematically using the camber gain/loss when the steering is turned?