Dan , for wheel base measurement , Truckmaker is right on the $ . Bridge law only specifies the min distance between axles for a specific weight to be carried . I'm not sure how the manufacture figures the twin steer set up . I think it is still from the front most front axle
. IIRC from pics of what I saw your building , I don't think you need to worry about that unless it's different . If your going military , I don't think they worry about bridge law
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