I'm wondering if you'd like to know just for personal reasons, or do you need to provide an 'official' weight rating number for Title & Registration fee / taxation purposes?
Given a choice between slightly different numbers from multiple sources, a lower GVRW should (obviously) result in lower fees you need to pay.
Here is a google search link on the words "1959 Ranchero GVRW", hopefully it works for you.
https://www.google.com/search?q=1959...obile&ie=UTF-8
I glanced thru the first several websites and found the weight of the vehicle listed but did not notice a number for the vehicle plus payload, GVRW.
Perhaps another member on this forum has the information you need and can be more helpful.
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