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Your caster is higher on the left than the right, that's probably why it's pulling. I like to have about 1/2-3/4 more caster on the right to compensate for the crown in the road. You could try a wedge shim between the spring and front end to try and even it up, if that don't work you can put an offset upper ball joint seat in it if you can find one. Honestly though, the first thing I would try would be switching the front tires from side to side to make sure it's not tire conicity or a radial pull.